Slightly OT: MARC

Hi there,

Due to the recent discussion, I read some literature about MARC ([1]
might be a good starting point) and I wonder if MARC is that bad. If I
understood it correctly, MARC was designed for exchanging data (among
other goals). But how do librarian *exchange* the MARC records if they
do not merge?

From what I've read, the

    010 tag: marks the Library of Congress Control Number (LCCN)
    020 tag: marks the International Standard Book Number (ISBN)

seem to be promising. Are the LCCN or ISBN are normative?

[1] <http://www.loc.gov/marc/umb/>

Thanks and best regards,
Lars

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Semagia
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