If you plan to sell your book to libraries, you’ll need a Library of Congress Catalog Number, aka an LCCN.
You can order your own through the website of the Cataloging in Publication Division of the Library of Congress. The best news is that applying for an LCCN is free, so it makes sense to simply add an LCCN when you self-publish a book.
A book must be longer than 50 pages to qualify for an advance purchase of LCCN. Because of this, many children’s books typically don’t qualify.
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My name is Rob Bignell. I’m an affordable, professional editor who runs Inventing Reality Editing Service, which meets the manuscript needs of writers both new and published. I also offer a variety of self-publishing services. During the past decade, I’ve helped more than 300 novelists and nonfiction authors obtain their publishing dreams at reasonable prices. I’m also the author of the 7 Minutes a Day… writing guidebooks, four nonfiction hiking guidebook series, and the literary novel Windmill. Several of my short stories in the literary and science fiction genres also have been published.