This book helps the collector distinguish unusal varieites, hub design changes, date-by-date analysis, how die varieties are made, double dies, over mint marks, and repunched mintmarks. Kevin Flynn. ISBN: 0967965527. Pub Date: 7/1/2002. Edition: 2nd. Binding: Paperback. Size: 8.5x11. Pages: 182. Case: 30 .