Books About Barcodes

Lines of Communication by Craig Harmon
(Helmers Publishing)
Includes quite a bit of technical information that can be useful to programmers.  We believe this book has been out of print for a while, but used copies are often available on line.
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The Bar Code Book by Roger C. Palmer
(Helmers Publishing, ISBN 0-911261-09-5, 386 pages)
This book offers an introduction to data entry techniques and the history of barcodes, and a detailed description of the technology which underpins the various types of barcodes in common use.  Chapters describe all aspects, including printing, scanning, verification, and more.  Over 100 pages of appendices cover technical details of the most widely used barcode symbologies.
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Punched Cards to Bar Codes by Benjamin Nelson
(Helmers Publishing, ISBN 0-911261-12-5, 434 pages)
An excellent reference on the history of barcodes, this book includes descriptions of over 260 different types of barcodes. We have successfully used this book to identify samples of little-used codes that have been sent to us.
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