Bibliographic Framework Initiative (Library of Congress)

The Library of Congress > BIBFRAME > MARC 21 to BIBFRAME 2.0 Conversion Specifications

The following specifications were developed to support a pilot in the use of BIBFRAME 2.0 at the Library of Congress. They specify the conversion of MARC Bibliographic records to BIBFRAME Work, Instance and Item descriptions, and MARC Authority records for titles and name/titles to BIBFRAME Work descriptions.

MARC Bibliographic Conversion Specifications

MARC Title Authority Conversion Specifications

Usage Notes

These specifications are written from the perspective of MARC so that each element in MARC would at least be considered, even if not converted. The specifications are presented in MS Excel files accompanied by a few explanatory specifications in MS Word.  If there is little or no use of an element in the Library of Congress records, the Specifications usually say “nac” (no attempt to convert) in the conversion column. Others may want to augment the specifications to address “nac” elements. Some elements in a MARC record are not relevant outside the MARC environment so they are simply marked “ignore”.

A shorthand is used for the specification of the conversion from MARC to BIBFRAME RDF. The shorthand uses W for Work, I for Instance, but Item for Item. The Specifications use the vocabularies that are in in a number of cases, especially for names, subjects, genre, and 007 and 008 data.

The Specifications also use properties with strings for data that will be used when trying to match and merge data to change the data to conform to the BIBFRAME Work and Instance models and to identify labels and RWOs in the MADS name and subject files. These local elements from the bflc: namespace are included in the conversion of names and titles. The Library of Congress uses these elements through multiple conversions until we are satisfied with the file conversion. These “helper” local elements will be eliminated from the RDF when the merge and match is complete unless we see a need to keep certain ones for data that will continue to come into our BIBFRAME environment from MARC.

The Specifications will be changed as needed throughout the BIBFRAME 2.0 Pilot. Revisions to specifications will be marked and the file name and the title on the document will indicate a revision (e.g., R1, R2, R3, …) and revision date.

The MARC Authority record conversion is contained in one specification that omits MARC fields that are not applicable to title authorities.  It also references the specifications for conversion of MARC Bibliographic records and/or repeats them as needed.  The MARC Authority conversion for titles uses the Process Notes specification that has been augmented to add notes needed for conversion of MARC title Authorities to BIBFRAME Works.