I don’t have much of a memory for exact details of the rules and formats for cataloging. At least not yet. So, I have to look everything up over and over again, just to be sure I am doing it right.

That is where this resource comes in handy.

OCLC Bibligraphic Formats and Standards (http://www.oclc.org/bibformats/default.htm

It outlines each MARC field, its indicators and subfields, and the appropriate way to code and punctuate each, giving examples to match. I use it about 100 times a day.