MARC bibliographic records should comply with standards as set forth in these documents:

Anglo-American Cataloguing Rules (2nd ed., 2002 revision)

MARC 21 Format for Bibliographic Data
http://www.loc.gov/marc/bibliographic/ecbdhome.html

Bibliographic Formats and Standards
http://www.oclc.org/bibformats/default.htm

Library of Congress Rule Interpretations
http://www.loc.gov/catdir/cpso/currlcri.html

Library of Congress Subject Headings
http://authorities.loc.gov/

Subject Cataloging Manual: Subject Headings

Medical Subject Headings (MeSH)
http://www.nlm.nih.gov/mesh/meshhome.html

CONSER Documentation
http://www.loc.gov/catdir/cpso/conser.html

Other documents or sites which may assist you in cataloging include the MARC Standards site from the Library of Congress - Network Development and MARC Standards Office
(http://www.loc.gov/marc/marc.html) and The Library of Congress Cataloging Policy & Support Office (http://www.loc.gov/catdir/cpso/).

Each MOBIUS library is required to exercise authority control over its own database. Libraries may use the Library of Congress Authorities (http://authorities.loc.gov/) and MARC 21 Format for Authority Data (http://www.loc.gov/marc/authority/ecadhome.html)
websites to assist in authority control.