Notation declarations are made with Notation elements nested in the XSchema element.
<!ELEMENT Notation (Doc?, More?) >
Name NMTOKEN #REQUIRED
id ID #IMPLIED
PubidLiteral CDATA #IMPLIED
SystemLiteral CDATA #IMPLIED>
Notations may include a public identifier or a system literal, or both. XSchema processors should ignore Notation elements that contain neither. Public identifiers and system literals should conform to the rules in Section 4.7 of the XML 1.0 Specification.