Design Type A6. 1d Drommedaris, 1926-43. Measurements of overprint: Edwin Mueller, “new philatelic Research”, Mercury Stamp Journal, Vol. 2, Whole No. 14 (July 1950): 42; correction at “Question Box” at Whole No. 15 (October 1950): 71. How to identify the issues: E. de H. Rowntree, “Identifying the South African 1d Pictorial”, Stamp Collecting, Vol. 70 (July 3, 1948): 289,90.
C1-C4. Mail Plane Airmail issue of 1925. Alexander F. Newall, Airmail Stamps: Fakes & Forgeries, pp.287,88 (Sanabria Airmail Catalogue 1-4). Varro Tyler, Linn’s Focus on Forgeries: A Guide to Forgeries of Common Stamps, Revised, Expanded Edition, pp.275-78.
Madame Joseph fraudulent postmark, 11 DE/00. Derek Worboys and Roger B. West, Madame Joseph Forged Postmarks, p.95.