Marler, George C., Canada notes on the 1911-1925 Series, J. W. Stowell Printing Company, 1949
Marler, George C., The Admiral Issue of Canada, State College: American Philatelic Society, 1982
Baxter, James H., Printing Postage Stamps by Line Engraving, Lawrence: American Philatelic Society, 1939
Matte, Raymond, Geo. V - 1912 - 2 Red - Admiral, Vol. 1, 1975
Matte, Raymond, Geo. V - 1912 - 2 Red - Admiral, Vol. 2, 1976
Matte, Raymond, Geo. V - 1912 - 2 Red - Admiral, Vol. 3, 1977
Reiche, Hans., Canada The Admiral Stamps of 1911 to 1925, 1965
Reiche, Hans. Canada The Admiral Stamps of 1911 to 1925, Part 2, 1965
Admiral Study Group, the web page of the BNAPS Admiral Study Group.
Online Resources of the BNAPS Admiral Study Group.
Boggs, Winthrop S., The Postage Stamps and Postal History of Canada. Kalamazoo, Michigan: Chambers Publishing Co., 1945
Jarrett, Fred, Stamps of British North America, Toronto: W. R. Phillips & Co., 1929
"Dots and Scratches", the journal of the Re-entries and Constant Plate Varieties Study Group of BNAPS