1913 Romanov Tercentenary 1k brown, complete die proof on chalk surfaced paper, with the names of designer and engraver beneath the picture, pencil « 52 » on reverse, possibly from the Tsar collection sold by R. Lowe auction in 1935 – Lot 16 described as “ 1 kopek: Three die proofs in shades of chestnut brown” published in the Yamschik-Post Rider 1983, No 12, page 12, fine and rare.