CL42, 1927 25c Yukon Airways & Exploration Co Ltd,,proofs assortment featuring a reverse die proof in black on thick card 99 x 76mm (Unitrade $450), plus bottom left and bottom right trial color proofs in pale blue (Unitrade $150 each), plus unlisted orange, orange red and magenta; also includes an NH single of the issued stamp and a single tied to April 13, 1928, copy of "The White Horse Star" newspaper, very fine group