Here is the culprit!
Poster Number: PP 1006
Category: World War II
Poster Notes: Poster was issued by the German Army during their occupation of Yugoslavia; Flags depicted are Great Britain, United States and the Soviet Union.
Media Size: 23x16.5
Poster Type: Offset
Publishing Date: c.1943
Technical Information on Poster: Pr B. XV/XI 5/235 Ba.
Catalog Notes: PP 1006 World War II c
Language: Serbian
Artist: Hanisch, Bruno —
Publisher: Publisher not indicated —