EN ISO 19136:2009

SLOVENSKI STANDARD
01-maj-2009
*HRJUDIVNHLQIRUPDFLMH-H]LN]DR]QDþHYDQMHJHRJUDIVNLKSRGDWNRY*0/,62

Geographic information - Geography Markup Language (GML) (ISO 19136:2007)
Geoinformation - Geography Markup Language (GML) (ISO 19136:2007)
Information géographique - Langage de balisage en géographie (GML) (ISO
19136:2007)
Ta slovenski standard je istoveten z: EN ISO 19136:2009
ICS:
35.240.70 Uporabniške rešitve IT v IT applications in science
znanosti
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 19136
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2009
ICS 35.240.70
English Version
Geographic information - Geography Markup Language (GML)
(ISO 19136:2007)
Information géographique - Langage de balisage en
géographie (GML) (ISO 19136:2007)
This European Standard was approved by CEN on 25 January 2009.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 19136:2009: E
worldwide for CEN national Members.

Contents Page
Foreword .3

Foreword
The text of ISO 19136:2007 has been prepared by Technical Committee ISO/TC 211 “Geographic
information/Geomatics” of the International Organization for Standardization (ISO) and has been taken over
as EN ISO 19136:2009 by Technical Committee CEN/TC 287 “Geographic Information” the secretariat of
which is held by NEN.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by September 2009, and conflicting national standards shall be
withdrawn at the latest by September 2009.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of ISO 19136:2007 has been approved by CEN as a EN ISO 19136:2009 without any modification.

INTERNATIONAL ISO
STANDARD 19136
First edition
2007-09-01
Geographic information — Geography
Markup Language (GML)
Information géographique — Langage de balisage en géographie
(GML)
Reference number
ISO 19136:2007(E)
©
ISO 2007
ISO 19136:2007(E)
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©  ISO 2007
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ii © ISO 2007 – All rights reserved

ISO 19136:2007(E)
Contents Page
Foreword. vi
Introduction . vii
1 Scope . 1
2 Conformance. 1
2.1 Conformance requirements. 1
2.2 Conformance classes related to GML application schemas. 2
2.3 Conformance classes related to GML profiles . 2
2.4 Conformance classes related to GML documents. 4
2.5 Conformance classes related to software implementations. 4
3 Normative references . 4
4 Terms and symbols . 5
4.1 Terms and definitions. 5
4.2 Symbols and abbreviated terms . 12
5 Conventions . 13
5.1 XML namespaces. 13
5.2 Versioning . 14
5.3 Deprecated parts of previous versions of GML. 14
5.4 UML notation. 14
5.5 XML Schema. 16
6 Overview of the GML schema. 16
6.1 GML schema. 16
6.2 GML application schemas . 16
6.3 Relationship between the ISO 19100 series of International Standards, the GML schema
and GML application schemas . 17
6.4 Organization of this International Standard.18
6.5 Deprecated and experimental schema components. 19
7 GML schema — General rules and base schema components . 20
7.1 GML model and syntax. 20
7.2 gmlBase schema components . 22
8 GML schema — Xlinks and basic types . 33
8.1 Xlinks — Object associations and remote properties . 33
8.2 Basic types . 34
9 GML schema — Features. 43
9.1 General concepts. 43
9.2 Relationship with ISO 19109. 43
9.3 Features . 43
9.4 Standard feature properties. 44
9.5 Geometry properties. 46
9.6 Topology properties . 48
9.7 Temporal properties . 48
9.8 Defining application-specific feature types .49
9.9 Feature collections . 50
9.10 Spatial reference system used in a feature or feature collection . 52
10 GML schema — Geometric primitives. 52
10.1 General concepts. 52
10.2 Abstract geometric primitives . 58
10.3 Geometric primitives (0-dimensional) . 59
ISO 19136:2007(E)
10.4 Geometric primitives (1-dimensional). 60
10.5 Geometric primitives (2-dimensional). 72
10.6 Geometric primitives (3-dimensional). 81
11 GML schema — Geometric complex, geometric composites and geometric aggregates . 83
11.1 Overview . 83
11.2 Geometric complex and geometric composites. 84
11.3 Geometric aggregates . 86
12 GML schema — Coordinate reference systems schemas. 91
12.1 Overview . 91
12.2 Reference systems . 93
12.3 Coordinate reference systems. 95
12.4 Coordinate systems. 103
12.5 Datums . 110
12.6 Coordinate operations. 117
13 GML schema — Topology. 129
13.1 General concepts . 129
13.2 Abstract topology . 130
13.3 Topological primitives . 130
13.4 Topological collections . 135
13.5 Topology complex . 137
14 GML schema — Temporal information and dynamic features. 139
14.1 General concepts . 139
14.2 Temporal schema. 140
14.3 Temporal topology schema . 148
14.4 Temporal reference systems . 151
14.5 Representing dynamic features. 158
15 GML schema — Definitions and dictionaries. 162
15.1 Overview . 162
15.2 Dictionary schema . 162
16 GML schema — Units, measures and values. 165
16.1 Introduction . 165
16.2 Units schema. 165
16.3 Measures schema . 171
16.4 Value objects schema. 172
17 GML schema — Directions. 179
17.1 Direction schema . 179
17.2 direction, DirectionPropertyType . 179
17.3 DirectionVectorType . 180
17.4 DirectionDescriptionType . 180
18 GML schema — Observations . 181
18.1 Observations . 181
18.2 Observation schema. 182
19 GML schema — Coverages. 185
19.1 The coverage model and representations. 185
19.2 Grids schema. 188
19.3 Coverage schema . 191
20 Profiles . 205
20.1 Profiles of GML and application schemas. 205
20.2 Definition of profile . 205
20.3 Relation to application schema . 205
20.4 Rules for elements and types in a profile. 206
20.5 Rules for referencing GML profiles from application schemas . 207
20.6 Recommendations for application schemas using GML profiles. 207
20.7 Summary of rules for GML profiles. 208
iv © ISO 2007 – All rights reserved

ISO 19136:2007(E)
21 Rules for GML application schemas. 208
21.1 Instances of GML objects . 208
21.2 GML application schemas . 209
21.3 Schemas defining Features and Feature Collections. 212
21.4 Schemas defining spatial geometries . 213
21.5 Schemas defining spatial topologies . 214
21.6 Schemas defining time. 215
21.7 Schemas defining coordinate reference systems. 215
21.8 Schemas defining coverages . 216
21.9 Schemas defining observations. 218
21.10 Schemas defining dictionaries and definitions . 219
21.11 Schemas defining values. 220
21.12 GML profiles of the GML schema. 220
Annex A (normative) Abstract test suites for GML application schemas, GML profiles and GML
documents. 223
Annex B (normative) Abstract test suite for software implementations. 238
Annex C (informative) GML schema. 242
Annex D (normative)  Implemented Profile of the ISO 19100 series of International Standards and
Extensions. 244
Annex E (normative) UML-to-GML application schema encoding rules . 309
Annex F (normative) GML-to-UML application schema encoding rules . 329
Annex G (informative) Guidelines for subsetting the GML schema . 339
Annex H (informative) Default styling . 352
Annex I (informative) Backwards compatibility with earlier versions of GML. 363
Annex J (informative) Modularization and dependencies. 380
Bibliography . 382
Index. 384

ISO 19136:2007(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 19136 was prepared by Technical Committee ISO/TC 211, Geographic information/Geomatics.
The Geography Markup Language (GML) was originally developed within the Open Geospatial Consortium,
Inc. (OGC). ISO 19136 was prepared by ISO/TC 211 jointly with OGC.
vi © ISO 2007 – All rights reserved

ISO 19136:2007(E)
Introduction
Geography Markup Language is an XML grammar written in XML Schema for the description of application
schemas as well as the transport and storage of geographic information.
The key concepts used by Geography Markup Language (GML) to model the world are drawn from the
ISO 19100 series of International Standards and the OpenGIS Abstract Specification.
A feature is an “abstraction of real world phenomena” (ISO 19101); it is a geographic feature if it is associated
with a location relative to the Earth. So a digital representation of the real world may be thought of as a set of
features. The state of a feature is defined by a set of properties, where each property may be thought of as a
{name, type, value} triple.
The number of properties a feature may have, together with their names and types, is determined by its type
definition. Geographic features with geometry are those with properties that may be geometry-valued. A
feature collection is a collection of features that may itself be regarded as a feature; as a consequence a
feature collection has a feature type and thus may have distinct properties of its own, in addition to the
features it contains.
Following ISO 19109, the feature types of an application or application domain is usually captured in an
application schema. A GML application schema is specified in XML Schema and can be constructed in two
different and alternative ways:
⎯ by adhering to the rules specified in ISO 19109 for application schemas in UML, and conforming to both
the constraints on such schemas and the rules for mapping them to GML application schemas specified
in this International Standard;
⎯ by adhering to the rules for GML application schemas specified in this International Standard for creating
a GML application schema directly in XML Schema.
Both ways are supported by this International Standard. To ensure proper use of the conceptual modelling
framework of the ISO 19100 series of International Standards, all application schemas are expected to be
modelled in accordance with the General Feature Model as specified in ISO 19109. Within the ISO 19100
series, UML is the preferred language by which to model conceptual schemas.
GML specifies XML encodings, conformant with ISO 19118, of several of the conceptual classes defined in
the ISO 19100 series of International Standards and the OpenGIS Abstract Specification. These conceptual
models include those defined in:
⎯ ISO/TS 19103 — Conceptual schema language (units of measure, basic types);
⎯ ISO 19107 — Spatial schema (geometry and topology objects);
⎯ ISO 19108 — Temporal schema (temporal geometry and topology objects, temporal reference systems);
⎯ ISO 19109 — Rules for application schemas (features);
⎯ ISO 19111 — Spatial referencing by coordinates (coordinate reference systems);
⎯ ISO 19123 — Schema for coverage geometry and functions.
The aim is to provide a standardized encoding (i.e. a standardized implementation in XML) of types specified
in the conceptual models specified by the International Standards listed above. If every application schema
were encoded independently and the encoding process included the types from, for example, ISO 19108, then,
ISO 19136:2007(E)
without unambiguous and completely fixed encoding rules, the XML encodings would be different. Also, since
every implementation platform has specific strengths and weaknesses, it is helpful to standardize XML
encodings for core geographic information concepts modelled in the ISO 19100 series of International
Standards and commonly used in application schemas.
In many cases, the mapping from the conceptual classes is straightforward, while in some cases the mapping
is more complex (a detailed description of the mapping is part of this International Standard).
In addition, GML provides XML encodings for additional concepts not yet modelled in the ISO 19100 series of
International Standards or the OpenGIS Abstract Specification, for example, dynamic features, simple
observations or value objects.
Predefined types of geographic feature in GML include coverages and simple observations.
A coverage is a subtype of feature that has a coverage function with a spatiotemporal domain and a value set
range of homogeneous 1- to n-dimensional tuples. A coverage may represent one feature or a collection of
features “to model and make visible spatial relationships between, and the spatial distribution of, Earth
[20]
phenomena” (OGC Abstract Specification Topic 6 ) and a coverage “acts as a function to return values
from its range for any direct position within its spatiotemporal domain” (ISO 19123).
An observation models the act of observing, often with a camera or some other procedure, a person or some
form of instrument (Merriam-Webster Dictionary: “an act of recognizing and noting a fact or occurrence often
involving measurement with instruments”). An observation is considered to be a GML feature with a time at
which the observation took place, and with a value for the observation.
A reference system provides a scale of measurement for assigning values to a position, time or other
descriptive quantity or quality.
A coordinate reference system consists of a set of coordinate system axes that is related to the Earth through
a datum that defines the size and shape of the Earth.
A temporal reference system provides standard units for measuring time and describing temporal length or
duration.
A reference system dictionary provides definitions of reference systems used in spatial or temporal
geometries.
Spatial geometries are the values of spatial feature properties. They indicate the coordinate reference system
in which their measurements have been made. The “parent” geometry element of a geometric complex or
geometric aggregate makes this indication for its constituent geometries.
Temporal geometries are the values of temporal feature properties. Like their spatial counterparts, temporal
geometries indicate the temporal reference system in which their measurements have been made.
Spatial or temporal topologies are used to express the different topological relationships between features.
A units of measure dictionary provides definitions of numerical measures of physical quantities, such as length,
temperature and pressure, and of conversions between units.

viii © ISO 2007 – All rights reserved

INTERNATIONAL STANDARD ISO 19136:2007(E)

Geographic information — Geography Markup Language (GML)
1 Scope
The Geography Markup Language (GML) is an XML encoding in compliance with ISO 19118 for the transport
and storage of geographic information modelled in accordance with the conceptual modelling framework used
in the ISO 19100 series of International Standards and including both the spatial and non-spatial properties of
geographic features.
This International Standard defines the XML Schema syntax, mechanisms and conventions that:
⎯ provide an open, vendor-neutral framework for the description of geospatial application schemas for the
transport and storage of geographic information in XML;
⎯ allow profiles that support proper subsets of GML framework descriptive capabilities;
⎯ support the description of geospatial application schemas for specialized domains and information
communities;
⎯ enable the creation and maintenance of linked geographic application schemas and datasets;
⎯ support the storage and transport of application schemas and datasets;
⎯ increase the ability of organizations to share geographic application schemas and the information they
describe.
Implementers may decide to store geographic application schemas and information in GML, or they may
decide to convert from some other storage format on demand and use GML only for schema and data
transport.
NOTE If an ISO 19109 conformant application schema described in UML is used as the basis for the storage and
transportation of geographic information, this International Standard provides normative rules for the mapping of such an
application schema to a GML application schema in XML Schema and, as such, to an XML encoding for data with a
logical structure in accordance with the ISO 19109 conformant application schema.
2 Conformance
2.1 Conformance requirements
Clauses 7 to 19 of this International Standard specify XML Schema components, i.e. the GML schema, which
shall be used in GML application schemas in accordance with Clause 21. Clause 20 specifies rules for the
specification of a GML profile that may be defined for use in a GML application schema.
Few applications will require the full range of capabilities described by the GML schema. This clause,
therefore, defines a set of conformance classes that will support applications whose requirements range from
the minimum necessary to define simple feature types to full use of the GML schema.
ISO 19136:2007(E)
Most of the schema components specified in this International Standard implement concepts defined in the
ISO 19100 series of International Standards. In these cases, the conformance classes defined in this
International Standard are based on the conformance classes defined in the corresponding standard.
Any GML application schema, GML profile or software implementation claiming conformance with one of the
conformance classes shall pass all test cases of the corresponding abstract test suite.
Any software implementation claiming conformance to this International Standard shall document the GML
profile supported by the implementation. The GML profile shall pass all mandatory test cases of the abstract
test suite corresponding to GML profiles.
2.2 Conformance classes related to GML application schemas
GML application schemas claiming conformance to this International Standard shall conform to the rules
specified in Clauses 7 to 21 and pass all relevant test cases of the abstract test suite in A.1.
Depending on the characteristics of a GML application schema, 12 conformance classes are distinguished.
Table 1 lists these classes and the corresponding subclause of the abstract test suite.
Table 1 — Conformance classes related to GML application schemas
Subclause of the
Conformance class
abstract test suite
All GML application schemas A.1.1
GML application schemas converted from an ISO 19109 application schema in UML A.1.2
GML application schemas to be converted to an ISO 19109 application schema in UML A.1.3
GML application schemas defining features and feature collections A.1.4
GML application schemas defining spatial geometries A.1.5
GML application schemas defining spatial topologies A.1.6
GML application schemas defining time A.1.7
GML application schemas defining coordinate reference systems A.1.8
GML application schemas defining coverages A.1.9
GML application schemas defining observations A.1.10
GML application schemas defining dictionaries and definitions A.1.11
GML application schemas defining values A.1.12

2.3 Conformance classes related to GML profiles
The requirements of an application schema determine the XML Schema components from the GML schema
that shall be included in a GML profile. GML profiles claiming conformance to this International Standard shall
satisfy the requirements of the abstract test suite in A.2.
Depending on the contents and requirements concerning a specific GML profile, 31 conformance classes are
distinguished. Table 2 lists these classes and the corresponding subclause of the abstract test suite.
2 © ISO 2007 – All rights reserved

ISO 19136:2007(E)
Table 2 — Conformance classes related to GML profiles
Subclause of the
Conformance class
abstract test suite
All GML profiles A.2.1
Geometric primitives (spatial) — 0-dimensional A.2.2.1.1
Geometric primitives (spatial) — 0/1-dimensional A.2.2.1.2
Geometric primitives (spatial) — 0/1/2-dimensional A.2.2.1.3
Geometric primitives (spatial) — 0/1/2/3-dimensional A.2.2.1.4
Geometric complexes (spatial) — 0/1-dimensional A.2.3.1.1
Geometric complexes (spatial) — 0/1/2-dimensional A.2.3.1.2
Geometric complexes (spatial) — 0/1/2/3-dimensional A.2.3.1.3
Topologic complexes (spatial) — 0/1-dimensional A.2.4.1.1
Topologic complexes (spatial) — 0/1/2-dimensional A.2.4.1.2
Topologic complexes (spatial) — 0/1/2/3-dimensional A.2.4.1.3
Topologic complexes with geometric realization (spatial) — 1-dimensional A.2.5.1.1
Topologic complexes with geometric realization (spatial) — 2-dimensional A.2.5.1.2
Topologic complexes with geometric realization (spatial) — 3-dimensional A.2.5.1.3
Coordinate reference systems A.2.6
Coordinate operations between two coordinate reference systems A.2.7
Temporal geometry — 0-dimensional A.2.8.1
Temporal geometry — 0/1-dimensional A.2.8.2
Temporal topology A.2.9
Temporal reference systems A.2.10
Dynamic features A.2.11
Dictionaries A.2.12
Units dictionaries A.2.13
Observations A.2.14
Abstract coverage A.2.15.1
Discrete point coverage A.2.15.2
Discrete curve coverage A.2.15.3
Discrete surface coverage A.2.15.4
Discrete solid coverage A.2.15.5
Grid coverage A.2.15.6
Continuous coverage A.2.15.7
Curve implementations, for those GML profiles including 1-dimensional spatial geometry objects, shall always
include a “linear” interpolation technique. Surface implementations, for those GML profiles including
2-dimensional spatial geometry objects, shall always include a “planar” interpolation technique. Additional
curve and surface interpolation mechanisms are optional but, if implemented, they shall follow the definition
included in this International Standard.
NOTE 1 Compare these conformance classes with ISO 19107:2003, Clause 2, ISO 19108:2002, 2.2, and

ISO 19123:2005, Clause 2.
ISO 19136:2007(E)
NOTE 2 A GML profile conforming to the three conformance classes “Geometric primitives (spatial) — 0-dimensional”,
“Geometric primitives (spatial) — 0/1-dimensional”, and “Geometric primitives (spatial) — 0/1/2-dimensional” (in addition to
conformance class “All GML profiles”) conforms to the spatial profile defined in ISO 19137:2007 and the respective
conformance tests in ISO 19137:2007, B.1, B.2 and B.3.
2.4 Conformance classes related to GML documents
GML documents claiming conformance to this International Standard shall conform to the rules specified in
Clauses 7 to 21 and pass all relevant test cases of the abstract test suite in A.3.
2.5 Conformance classes related to software implementations
Software implementations reading or writing GML or GML application schemas claiming conformance to this
International Standard shall pass all of the corresponding abstract test suites described in the abstract test
suite in Annex B.
Depending on the capabilities of the implementation, 11 conformance classes are distinguished. Table 3 lists
these classes and the corresponding subclause of the abstract test suite.
Table 3 — Conformance classes related to implementations
Subclause of the
Conformance class
abstract test suite
All software implementations B.1
Support for remote simple Xlinks B.2.1
Support for extended Xlinks B.2.2
Support for nillable properties B.2.3
Support for units of measurement B.2.4
Support for ownership semantics of properties B.2.5
Metadata properties B.2.6
Support for GML profiles in instance validation B.2.7
Writing GML B.3
Reading GML B.4
Writing GML application schemas B.5
Reading GML application schemas B.6
3 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 8601, Data elements and interchange formats — Information interchange — Representation of dates and
times
ISO/IEC 11404:1996, Information technology — Programming languages, their environments and system
software interfaces — Language-independent datatypes
ISO/TS 19103:2005, Geographic information — Conceptual schema language
ISO 19107:2003, Geographic information — Spatial schema
4 © ISO 2007 – All rights reserved

ISO 19136:2007(E)
ISO 19108:2002, Geographic information — Temporal schema
ISO 19109:2005, Geographic information — Rules for application schema
ISO 19111:2007, Geographic information — Spatial referencing by coordinates
ISO 19115:2003, Geographic information — Metadata
ISO 19118:2005, Geographic information — Encoding
ISO 19123:2005, Geographic information — Schema for coverage geometry and functions
ISO/TS 19139, Geographic information — Metadata — XML schema implementation
ISO/IEC 19757-3, Information technology — Document Schema Definition Languages (DSDL) — Part 3:
Rule-based validation — Schematron
ISO 80000-3, Quantities and units — Part 3: Space and time
IETF RFC 2396, Uniform Resource Identifiers (URI): Generic Syntax (August 1998)
W3C XLink, XML Linking Language (XLink) Version 1.0, W3C Recommendation (27 June 2001)
W3C XML, Extensible Markup Language (XML) 1.0 (Third Edition), W3C Recommendation (4 February 2004)
W3C XML Namespaces, Namespaces in XML, W3C Recommendation (14 January 1999)
W3C XML Schema Part 1, XML Schema Part 1: Structures, W3C Recommendation (2 May 2001)
W3C XML Schema Part 2, XML Schema Part 2: Datatypes, W3C Recommendation (2 May 2001)
4 Terms and symbols
4.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
4.1.1
application schema
conceptual schema for data required by one or more applications
[ISO 19101:2002]
4.1.2
association
...