MarcXchange: The general XML schema for MARC formatted records. Prepared by Tommy Schomacker - version 1.1 - July 2007. MarcXchange is made as a generalization (mainly by weakening restrictions) of the MARCXML schema for MARC21. MARCXML is made by Corey Keith from the Library of Congress. The schema supports XML markup of MARC records as specified in ISO 2701. ISO 2709 defines the following general structure: Record Label - Directory - Record Identifier - Reference Fields - Data Fields. In the schema the element "leader" is used for ISO 2709 Record Label, the element "control field" for ISO 2709 Record Identifier and Reference Fields, and the element "data field" for ISO 2709 Data Fields. The schema has no counterpart to ISO 2709 Directory. Extensions and elucidations: The schema allows the usage of "data fields" for all legal tags, including 001 to 009, 00A to 00Z and 00a to 00z. Subfield identifiers may consist of 8 bits characters from ISO 10646 BMP row 00 (Basic Latin and Latin-1 Supplement). Two attributes are introduced to specify the content of a record - "format" to specify the MARC format, "type" to specify the kind of record. collection is a top level container element for 0 or many records record is a top level container element for all of the field elements which compose the record ISO 2709 Record Label, 24 octets ISO 2709 Record Identifier and Reference Fields ISO 2709 data fields