The following, in order:

• <object-id> Object Identifier, zero or more

• <label> Label (of an Equation, Figure, Reference, etc.), zero or one

• <caption> Caption of a Figure, Table, etc., zero or one

• <abstract> Abstract, zero or more

• <kwd-group> Keyword Group, zero or more

• Any combination of:

  • Accessibility Elements

    • <alt-text> Alternate Text Name (for a figure, etc.)

    • <long-desc> Long Description

  • Linking Elements

    • <email> Email Address

    • <ext-link> External Link

    • <uri> Uniform Resource Identifier (URI)

• One or more of any of:

  • <alternatives> Alternatives For Processing

  • <chem-struct> Chemical Structure (Display)

  • <code> Code

  • <graphic> Graphic

  • <media> Media Object

  • <preformat> Preformatted Text

  • <textual-form> Textual Form

• Any combination of:

  • Ownership Elements

    • <attrib> Attribution

    • <permissions> Permissions