PSE currently offers two publications oriented around the U.S. Design Numbering system. We offer A Guide to U.S. Design Numbers 1847-1947, a concise booklet illustrating USD numbers through No. 435, which corresponds to Scott No. 947. The Guide cross-references all USD and Scott numbers.
PSE also offers album pages, United States Postage Stamps by Design Type, The First Century, allowing collectors to begin and display a collection based on the USD numbering system.
All 19th and early 20th century USD numbers are shown at the following website:
http://www.rfrajola.com/SNS/SNSmajors.htm
This fall, PSE is planning to produce a special edition of the SMQ, using USD numbers and giving prices in nine grades for USD Nos. 1 through 238. We plan to update this edition annually.