1963 Sc 2850. 90 anniversary since the birth of Yu.M.Steklov. Scott 2815

1963. To the 90 anniversary since the birth of Yu.M.Steklov.
Catalog numbers: Scott 2815, Standard Collection 2850, Michel 2831, Yvert 2743.
Perforation: frame 11½.
Color: Black and red-lilac.
Printing: Photogravure.
Print run: 2,500,000.