1979 Sc 4887-4888 Soviet–Bulgarian Space Flight Scott 4747-4748

1979. Soviet–Bulgarian Space Flight.
Catalogs: Scott 4747-4748, Standard Collection 4887-4888, Michel 4837-4838, Yt 4593-4594.
Issued on: April 10, 1979.
Perforation: comb 11¾.
Printing: Offset lithography.
Size: 33 x 66 mm.
Colors: Multicolor.
Face value: 6 Russian kopek; 32 Russian kopek.
Quantity: 6,900,000; 4,600,000.