Lot 81246 – 1957/58 imperf proofs of the Russian first satelli

1957/58 imperf proofs of the Russian first satellites issue (single and pair) on RPR watermarked paper and frame proofs (single and block of four) of biologist, naturalist and Antarctic explorer Emil Racovita. Interesting items for the space and polar explorers topic. The block shows some yellowing possibly due to storage, otherwise fine condition of these scarce items.