A Tessloff translation of Fooled You, Bert!
Tessloff is a German publishing company, specializing in children's books (especially educational materials). They have published several Sesamstrasse titles, including translations of American books.
Founded in 1956, the company originally republished American comic titles such as Lassie and Tom and Jerry. They later shifted to licensing educational lines such as the "How & Why" series.
A subsidiary, Buchverlag Junge Welt (BJW), published a series of six Sesamstrasse storybooks for younger children in 2002. BJW merged back into the parent company in 2006.