EKU of a GL O.Z. Overprint
Unless a reader can document an earlier known use, the earliest reported use of any stamp with a GL O.Z. overprint is a 5c de p Leconte stamp (#201) postmarked June 27, 1914.
Unless a reader can document an earlier known use, the earliest reported use of any stamp with a GL O.Z. overprint is a 5c de p Leconte stamp (#201) postmarked June 27, 1914.