Nice school poster by H.J. Slyper "owls and birds of prey" with, among other things, little owl, short-eared owl, Osprey, Northern Harrier, etc.
The Netherlands 1960, H.J. Slyper, school poster on linen between two wooden sticks, dimension: 90 - 60 cm More
The Netherlands, 1959. Forest and meadow birds. Published by W.J. Thieme & Cie Zutphen, Illustrator H.J.Slijper, size 100 x 70 cm More