by Eric van der Vlist is published by O'Reilly & Associates (ISBN: 0596004214)
literal — Literal
literal ::= literalSegment ("~" literalSegment)+
datatypeName literal, datatypeName param exceptPattern, datatypes, default namespace, external, include, namespace
None
The literal production describes literals as several segments of literals contained by the tilde (~) symbol.
This text is released under the Free Software Foundation GFDL.