<?xml version="1.0" encoding="UTF-8" ?>
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Copyright © 2020 Mark Raynsford <code@io7m.com> http://io7m.com
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<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:xsl="http://www.w3.org/2001/XMLSchema"
elementFormDefault="qualified"
xmlns:dc="http://purl.org/dc/elements/1.1/"
xmlns:s="urn:com.io7m.structural:7:0"
targetNamespace="urn:com.io7m.structural:7:0">
<xsd:import namespace="http://purl.org/dc/elements/1.1/"
schemaLocation="dc.xsd"/>
<xsd:import namespace="http://www.w3.org/XML/1998/namespace"
schemaLocation="xml.xsd"/>
<xsd:simpleType name="uuidType">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A UUID value.
</xsd:documentation>
</xsd:annotation>
<xsd:restriction base="xsd:string">
<xsd:pattern value="[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}"/>
</xsd:restriction>
</xsd:simpleType>
<xsd:simpleType name="imageTextType">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of text that appears in image elements. This is required to be of non-zero length in order to ensure
that authors add useful text that will then be used in the 'alt' elements of XHTML generated from the document
sources.
</xsd:documentation>
</xsd:annotation>
<xsd:restriction base="xsd:string">
<xsd:minLength value="1"/>
</xsd:restriction>
</xsd:simpleType>
<xsd:simpleType name="typeType">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of type names. Type names are used to categorize elements and are somewhat analogous to CSS classes,
except that they are intended to be used for more than just styling documents.
</xsd:documentation>
</xsd:annotation>
<xsd:restriction base="xsd:string">
<xsd:pattern value="[a-zA-Z][a-zA-Z0-9_\.\-]*"/>
</xsd:restriction>
</xsd:simpleType>
<xsd:attributeGroup name="standardXMLAttributes">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The standard elements expected to appear in XML texts.
</xsd:documentation>
</xsd:annotation>
<xsd:attribute ref="xml:base"/>
<xsd:attribute ref="xml:lang"/>
</xsd:attributeGroup>
<xsd:attributeGroup name="tableOfContentAttributes">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The attributes used to describe tables of content.
</xsd:documentation>
</xsd:annotation>
<xsd:attribute name="tableOfContents"
use="optional"
default="true"
type="xsd:boolean">
<xsd:annotation>
<xsd:documentation xml:lang="en">
If the value of the attribute is 'true', then a table of contents will be generated in the respective element.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
<xsd:attribute name="tableOfContentsDepth"
use="optional"
default="3"
type="xsd:positiveInteger">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The maximum relative depth of sections and subsections that will appear in a generated table of contents.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:attributeGroup>
<xsd:element name="Image">
<xsd:annotation>
<xsd:documentation xml:lang="en">
An element used to describe an image. The text content of the image element SHOULD be used to provide an
accessible description of the image. This description is expected to be used by screen readers, and may also be
displayed by browsers if the referenced image cannot be loaded for any reason.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType mixed="true">
<xsd:simpleContent>
<xsd:extension base="s:imageTextType">
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the image.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
<xsd:attribute name="width"
type="xsd:nonNegativeInteger"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The width of the image.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
<xsd:attribute name="height"
type="xsd:nonNegativeInteger"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The height of the image.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
<xsd:attribute name="source"
type="xsd:anyURI"
use="required">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The source location of the image.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:extension>
</xsd:simpleContent>
</xsd:complexType>
</xsd:element>
<xsd:element name="Item">
<xsd:annotation>
<xsd:documentation xml:lang="en">
An item appearing in a list.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType mixed="true">
<xsd:sequence minOccurs="0"
maxOccurs="unbounded">
<xsd:group ref="s:ListContent"/>
</xsd:sequence>
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the list item.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:group name="ListContent">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The elements that may appear in list items.
</xsd:documentation>
</xsd:annotation>
<xsd:choice>
<xsd:element ref="s:Image"/>
<xsd:element ref="s:Link"/>
<xsd:element ref="s:LinkExternal"/>
<xsd:element ref="s:LinkFootnote"/>
<xsd:element ref="s:ListOrdered"/>
<xsd:element ref="s:ListUnordered"/>
<xsd:element ref="s:Term"/>
</xsd:choice>
</xsd:group>
<xsd:element name="ListOrdered">
<xsd:annotation>
<xsd:documentation xml:lang="en">
An ordered list.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType>
<xsd:sequence minOccurs="1"
maxOccurs="unbounded">
<xsd:element ref="s:Item"/>
</xsd:sequence>
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the list.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:element name="ListUnordered">
<xsd:annotation>
<xsd:documentation xml:lang="en">
An unordered list.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType>
<xsd:sequence minOccurs="1"
maxOccurs="unbounded">
<xsd:element ref="s:Item"/>
</xsd:sequence>
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the list.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:element name="Column">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A description of a column in a table.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType mixed="true">
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the column.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:element name="Columns">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A set of table column descriptions.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType>
<xsd:sequence minOccurs="1"
maxOccurs="unbounded">
<xsd:element ref="s:Column"/>
</xsd:sequence>
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the columns.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:group name="TableContent">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of content that may appear in table cells.
</xsd:documentation>
</xsd:annotation>
<xsd:choice>
<xsd:element ref="s:Link"/>
<xsd:element ref="s:LinkExternal"/>
<xsd:element ref="s:LinkFootnote"/>
<xsd:element ref="s:Term"/>
</xsd:choice>
</xsd:group>
<xsd:element name="Cell">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A cell in a table.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType mixed="true">
<xsd:sequence minOccurs="0"
maxOccurs="unbounded">
<xsd:group ref="s:TableContent"/>
</xsd:sequence>
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the cell.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:element name="Row">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A row of cells in a table.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType>
<xsd:sequence minOccurs="1"
maxOccurs="unbounded">
<xsd:element ref="s:Cell"/>
</xsd:sequence>
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the row.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:element name="Table">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A table. A table consists of a list of column definitions, followed by a sequence of rows consisting of the
table cells.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType>
<xsd:sequence>
<xsd:element ref="s:Columns"/>
<xsd:sequence minOccurs="1"
maxOccurs="unbounded">
<xsd:element ref="s:Row"/>
</xsd:sequence>
</xsd:sequence>
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the table.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:element name="Term">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A term acts as a simple container of one or more words in a sentence. Term elements can be used to denote the
semantics of words, such as wrapping the name of a mathematical function in a <Term type="function">
element.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType mixed="true">
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute type="s:typeType"
name="type"
use="required">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the term.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:element name="Link">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A Link element describes a link to an element within the current document. Links may only refer to elements that
contain an appropriate 'id' attribute.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType mixed="true">
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute type="s:uuidType"
name="target"
use="required">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The target of the link, which must be an element with an appropriate 'id' attribute.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the link.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:element name="LinkFootnote">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A LinkFootnote element describes a link to a footnote within the current section.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType mixed="true">
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute type="s:uuidType"
name="target"
use="required">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The target of the link, which must be a Footnote with a matching 'id' attribute.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the link.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:element name="LinkExternal">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A LinkExternal element describes a link to an external URI.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType mixed="true">
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute type="xsd:anyURI"
name="target"
use="required">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The target URI.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the link.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:element name="Verbatim">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A Verbatim element contains text that should be reproduced exactly, with almost all whitespace intact. Renderers
are permitted to trim leading and trailing whitespace.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType mixed="true">
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the verbatim text.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:group name="FormalItemContent">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of content that can appear in formal items.
</xsd:documentation>
</xsd:annotation>
<xsd:choice>
<xsd:element ref="s:Image"/>
<xsd:element ref="s:Link"/>
<xsd:element ref="s:LinkExternal"/>
<xsd:element ref="s:LinkFootnote"/>
<xsd:element ref="s:ListOrdered"/>
<xsd:element ref="s:ListUnordered"/>
<xsd:element ref="s:Table"/>
<xsd:element ref="s:Term"/>
<xsd:element ref="s:Verbatim"/>
</xsd:choice>
</xsd:group>
<xsd:group name="ParagraphContent">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of content that can appear in paragraphs.
</xsd:documentation>
</xsd:annotation>
<xsd:choice>
<xsd:element ref="s:Link"/>
<xsd:element ref="s:LinkExternal"/>
<xsd:element ref="s:LinkFootnote"/>
<xsd:element ref="s:ListOrdered"/>
<xsd:element ref="s:ListUnordered"/>
<xsd:element ref="s:Term"/>
</xsd:choice>
</xsd:group>
<xsd:element name="Metadata">
<xsd:annotation>
<xsd:documentation xml:lang="en">
An element containing document metadata.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType>
<xsd:group ref="dc:elementsGroup"/>
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
</xsd:complexType>
</xsd:element>
<xsd:element name="Paragraph">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A paragraph denotes a self-contained series of sentences.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType mixed="true">
<xsd:sequence minOccurs="0"
maxOccurs="unbounded">
<xsd:group ref="s:ParagraphContent"/>
</xsd:sequence>
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the paragraph.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
<xsd:attribute name="id"
type="s:uuidType"
use="optional"/>
</xsd:complexType>
</xsd:element>
<xsd:element name="FormalItem">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A formal item is analogous to a "figure" in printed text. Formal items are used to significant images, tables of
data, code listings, and other important objects into texts. They are considered to be at the same level of
structural significance as paragraphs.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType>
<xsd:group ref="s:FormalItemContent"/>
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute name="id"
type="s:uuidType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The unique identifier of the formal item.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
<xsd:attribute name="title"
type="xsd:string"
use="required">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The title of the formal item.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:group name="SubsectionContent">
<xsd:choice>
<xsd:element ref="s:Paragraph"/>
<xsd:element ref="s:FormalItem"/>
</xsd:choice>
</xsd:group>
<xsd:element name="Subsection">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A Subsection is a structural element that denotes a part of the document similar to a chapter.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType>
<xsl:choice>
<xsd:sequence minOccurs="1"
maxOccurs="unbounded">
<xsd:element ref="s:Subsection"/>
</xsd:sequence>
<xsd:sequence minOccurs="1"
maxOccurs="unbounded">
<xsd:group ref="s:SubsectionContent"/>
</xsd:sequence>
</xsl:choice>
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the subsection.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
<xsd:attribute name="id"
type="s:uuidType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The unique identifier of the subsection.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
<xsd:attribute name="title"
type="xsd:string"
use="required">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The title of the subsection.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:group name="FootnoteContent">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of content that may appear in footnotes.
</xsd:documentation>
</xsd:annotation>
<xsd:choice>
<xsd:element ref="s:Image"/>
<xsd:element ref="s:Link"/>
<xsd:element ref="s:LinkExternal"/>
<xsd:element ref="s:LinkFootnote"/>
<xsd:element ref="s:ListOrdered"/>
<xsd:element ref="s:ListUnordered"/>
<xsd:element ref="s:Table"/>
<xsd:element ref="s:Term"/>
<xsd:element ref="s:Verbatim"/>
</xsd:choice>
</xsd:group>
<xsd:element name="Footnote">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A Footnote is a note of referenc or comment usually placed at the bottom of a page. Footnotes may be referenced
by LinkFootnote elements.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType mixed="true">
<xsd:sequence minOccurs="0"
maxOccurs="unbounded">
<xsd:group ref="s:FootnoteContent"/>
</xsd:sequence>
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attribute name="id"
type="s:uuidType"
use="required">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The unique identifier of the footnote.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
</xsd:element>
<xsd:element name="Section">
<xsd:annotation>
<xsd:documentation xml:lang="en">
A Section is a structural element that denotes a part of the document similar to a chapter. Renderers that
produce multiple pages MUST insert whatever is analogous to a page break at the end of a section.
</xsd:documentation>
</xsd:annotation>
<xsd:complexType>
<xsd:sequence>
<xsd:choice>
<xsd:sequence minOccurs="1"
maxOccurs="unbounded">
<xsd:element ref="s:Section"/>
</xsd:sequence>
<xsd:sequence minOccurs="1"
maxOccurs="unbounded">
<xsd:element ref="s:Subsection"/>
</xsd:sequence>
<xsd:sequence minOccurs="1"
maxOccurs="unbounded">
<xsd:group ref="s:SubsectionContent"/>
</xsd:sequence>
</xsd:choice>
<xsd:sequence minOccurs="0"
maxOccurs="unbounded">
<xsd:element ref="s:Footnote"/>
</xsd:sequence>
</xsd:sequence>
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attributeGroup ref="s:tableOfContentAttributes"/>
<xsd:attribute name="type"
type="s:typeType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The type of the section.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
<xsd:attribute name="id"
type="s:uuidType"
use="optional">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The unique identifier of the section.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
<xsd:attribute name="title"
type="xsd:string"
use="required">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The title of the section.
</xsd:documentation>
</xsd:annotation>
</xsd:attribute>
</xsd:complexType>
<xsd:unique name="SectionFootnoteKey">
<xsd:annotation>
<xsd:documentation xml:lang="en">
All footnotes within a section must have unique identifiers.
</xsd:documentation>
</xsd:annotation>
<xsd:selector xpath="s:Footnote"/>
<xsd:field xpath="@id"/>
</xsd:unique>
<xsd:keyref name="SectionFootnoteReferences"
refer="s:SectionFootnoteKey">
<xsd:annotation>
<xsd:documentation xml:lang="en">
All footnote links must refer to footnotes that exist.
</xsd:documentation>
</xsd:annotation>
<xsd:selector xpath=".//s:LinkFootnote"/>
<xsd:field xpath="@target"/>
</xsd:keyref>
</xsd:element>
<xsd:element name="Document">
<xsd:annotation>
<xsd:documentation xml:lang="en">
The Document element represents the top-level structure of a document. The name 'document' is somewhat of a
misnomer, as nothing prevents the document from being structured as a book (with chapters, etc). The document
begins with standard Dublin Core metadata, and contains _either_ a series of sections _or_ a series of
subsections (but not both).
</xsd:documentation>
</xsd:annotation>
<xsd:complexType>
<xsd:sequence>
<xsd:element ref="s:Metadata"/>
<xsd:choice>
<xsd:sequence minOccurs="1"
maxOccurs="unbounded">
<xsd:element ref="s:Section"/>
</xsd:sequence>
<xsd:sequence minOccurs="1"
maxOccurs="unbounded">
<xsd:element ref="s:Subsection"/>
</xsd:sequence>
</xsd:choice>
<xsd:sequence minOccurs="0"
maxOccurs="unbounded">
<xsd:element ref="s:Footnote"/>
</xsd:sequence>
</xsd:sequence>
<xsd:attributeGroup ref="s:standardXMLAttributes"/>
<xsd:attributeGroup ref="s:tableOfContentAttributes"/>
</xsd:complexType>
<xsd:unique name="ItemIDsAreUnique">
<xsd:annotation>
<xsd:documentation xml:lang="en">
All 'id' attributes specified on objects within the document must be unique.
</xsd:documentation>
</xsd:annotation>
<xsd:selector xpath=".//s:FormalItem|.//s:Paragraph|.//s:Subsection|.//s:Section|.//s:Footnote"/>
<xsd:field xpath="@id"/>
</xsd:unique>
<xsd:unique name="LinkReferencesAreUnique">
<xsd:annotation>
<xsd:documentation xml:lang="en">
All 'id' attributes specified on objects within the document must be unique.
</xsd:documentation>
</xsd:annotation>
<xsd:selector xpath=".//s:FormalItem|.//s:Paragraph|.//s:Subsection|.//s:Section"/>
<xsd:field xpath="@id"/>
</xsd:unique>
<xsd:keyref name="LinkReferences"
refer="s:LinkReferencesAreUnique">
<xsd:annotation>
<xsd:documentation xml:lang="en">
All Link elements must refer to elements with existing 'id' attributes.
</xsd:documentation>
</xsd:annotation>
<xsd:selector xpath=".//s:Link"/>
<xsd:field xpath="@target"/>
</xsd:keyref>
<xsd:unique name="DocumentFootnoteKey">
<xsd:annotation>
<xsd:documentation xml:lang="en">
All 'id' attributes specified on footnotes within the document must be unique.
</xsd:documentation>
</xsd:annotation>
<xsd:selector xpath="s:Footnote"/>
<xsd:field xpath="@id"/>
</xsd:unique>
<xsd:keyref name="DocumentFootnoteReferences"
refer="s:DocumentFootnoteKey">
<xsd:annotation>
<xsd:documentation xml:lang="en">
All footnote references must refer to footnotes that exist.
</xsd:documentation>
</xsd:annotation>
<xsd:selector xpath="s:Subsection/*/s:LinkFootnote"/>
<xsd:field xpath="@target"/>
</xsd:keyref>
</xsd:element>
</xsd:schema>