• Watch our video on the Siegel Effect to test for Vegetable Tanned Leather
• Watch our video on the Ewald Effect- for Oil Tanned Leathers
• Leather for Libraries  recommendations for choosing the best leathers for bookbinding, per British Publication, approximately 1905
• Betty Haines re: Archival Bookbinding Leather
• Genuine Morocco published in Guild of Bookworkers. Author Steven Siegel

• Sample Sulfur Free Calf
• “The Romance of Leather”, published 1937, by Tanners’ Council of America – This document contains a wealth of information on the “basics” of leather
• Report of the Committee on Leather for Bookbinding, Royal Sociey of Arts (Great Britain), London, 1905 – please use Adobe Acrobat to open
• Affidavits for Archival Native Tanned Sokoto Leather    From 3 museum experts in Sokoto, Nigeria
• Native Tanned -Colored Archival Sokoto Leather
• Dry Fiber Ageing Analysis SF Calf vs 5 other bookbinding calfskins