Camp Knock Knock /
Betsy Duffey ; illustrated by Fiona Dunbar.
- New York : Delacorte Press, 1996.
- 47 p. : col. ill. ; 21 cm.
"A Yearling first choice chapter book"
Willie is king of the knock-knock jokes at summer camp, but to retain his title he must win the great riddle contest against Crow, who is best at everything.
"RL: 1.6"--Cover p. [4]. "Ages: 5-8"--Cover p. [4].