APA citiranje

(1990). Mathematics can be child's play / by James H. Humphrey, Joy N. Humphrey.

Chicago Style (17th ed.) Citation

Mathematics Can Be Child's Play / by James H. Humphrey, Joy N. Humphrey. 1990.

MLA citiranje

Mathematics Can Be Child's Play / by James H. Humphrey, Joy N. Humphrey. 1990.