Read-Me document for MoCat electronic file

After the Printing Act of 1895, the Government Printing Office (GPO) fulfilled 
the need for an official bibliography of current government agency publications 
through the Monthly Catalog.  More than a century later, the Monthly Catalog  
from GPO continues to document all the (Federal) Government publications that 
have been cataloged during the preceding month, where they can be obtained, and 
their individual cost (when applicable). In 1996,  government publications on 
Internet joined the ranks among the many works cataloged by GPO each year.

As a service to the varying needs of our users, the Monthly Catalog is now 
available in four different formats: in paper, on CD-ROM, as a searchable 
database online through GPO's World Wide Web site 
(http://www.access.gpo.gov/su_docs/dpos/adpos400.html) site, and as a text file 
on the Federal Bulletin Board (http://fedbbs.access.gpo.gov). 

The MARC-formatted data in the Monthly Catalog Federal Bulletin Board file is 
unspanned. The records in this file correspond with records currently sent from 
the Government Printing Office to the Library of Congress Cataloging 
Distribution Service. 

New files arrive on the Federal Bulletin Board on the Monday following the last 
Saturday of each month. The new file contains every record created, produced, or 
updated during that month on OCLC by GPO catalogers. The data set in each file 
appears as a continuous stream of unedited USMARC records (i.e. no line breaks 
separating one entry from another), and of records from previous months that 
have been revised and updated that month on OCLC. The records will be ordered by 
OCLC number. 

Each time a new monthly data set appears on the Federal Bulletin Board, it 
completely replaces the records from the preceding month. Bibliographic records 
remain on the Federal Bulletin Board until the succeeding monthly data set is 
uploaded. The individual bibliographic records of a file can be broken down into 
four sections: the leader, the directory, control fields and variable fields.

The Leader is fixed in length at 24 character positions. It tells how long a 
record will be. Character positions 20-23 are of notable importance, as the 
Entry map for the Directory is contained here. For detailed information about 
how the Leader is structured, please consult "USMARC Specifications for Record 
Structure, Character Sets, Tapes."  

The Directory, which always begins at the 24th character position of a record, 
consists of a series of fixed-length entries, each 12 character positions long, 
that contain the tag (00-02), length (03-06), and starting character position 
(07-11) of each control and variable field. All Directory entries are system 
generated. If questions arise, please consult "USMARC Specifications for Record 
Structure, Character Sets, Tapes" for more detailed information.

Following the Directory are the control fields. These contain control numbers 
and further data that are needed for the processing of machine-readable 
bibliographic records. All bibliographic records require 001,005, and 008 
control fields. It should be noted that indicators and subfield codes are absent 
from the control fields.

Variable fields, undoubtedly, will contain the information most of our users 
will hope to find. Among these variable fields,  you can find information 
concerning the title, author, publisher, OCLC number, and SuDocs number of a 
publication. The variable fields differ for each cataloging record. 

Should specific questions arise concerning the data, and how the fields of each 
record are coded, consult "USMARC Format for Bibliographic Data." This manual 
can be purchased, along with "USMARC Specifications for Record Structure,"  
through the Library of Congress, or found at libraries across the U.S.A. and the 
world. 

The GPO Access User Support Team is available to answer questions that concern 
downloading and other technical matters from 7 a.m. to 5:30 p.m., Eastern Standard 
Time, Monday through Friday (except Federal Holidays). You can reach the User 
Support Team by:

Phone Toll Free: 1-888-293-6498
        D.C. area : 1-202-512-1530

Internet e-mail: gpoaccess@gpo.gov

Fax: 1-202-512-1262