“The wise author applies for the LCCN before the book is printed.(Library of Congress Catalog Control Number) lccn One question that most authors don’t know to ask is, “How do I get the LCCN?”
What’s a LCCN? Good question—it’s the Library of Congress number that shows that you exist, and the one that any library that you are pitching your book to wants to know you have.
The good news is that these are free (although going through the two steps to get them can sometimes be a pain in the tush.”
Source: Authors: How to Get Your LCCN (Library of Congress Number) | Author U
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