K.L.M. Pictorial Map of Europe

A very colourful, promotional map jigsaw puzzle of Europe, mounted on plywood and cut in the fully interlocking style.

Estimated to be of c1950 manufacture, the map carries a signature in the lower left corner which appears to read "Seesink". I have not been able to identify an artist with this name, but it is a recognised Dutch surname.
nb. I have seen other copies of the map where an identity of "Leesink" has been given, but think that my interpretation of the signature seems more viable.

The puzzle is housed in a blue and yellow check-patterned box with lift-off lid. The box-base carries a label which indicates that the puzzle originally came with a picture inside, but this is sadly now absent.

Artist: Seesink?
Date: c1950
Brand: Ponda
Material: Plywood
Nationality: British-England
Pieces: 500
Size: 21 1/2" x 15 1/2"
Theme: Maps
Title: K.L.M. Pictorial Map of Europe