What is inside THIS box?

Daywalt, Drew Tallec, Olivier

Tallec, Olivier

Notes
1 volume (unpaged) : color illustrations ;24 cm.

Monkey has a big box, which he tells Cake has a cat inside, but only when the box is closed; Cake suggest that maybe it is a dinosaur instead, and the two friends puzzle over how they can solve the problem of finding out what is in the box, if it is always empty when opened.
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