APA

Barell J., . (1980). Playgrounds of our minds. New York: Teachers College Press.

Chicago

Barell John, . 1980. Playgrounds of our minds. New York: Teachers College Press.

Harvard

Barell J., . (1980). Playgrounds of our minds. New York: Teachers College Press.

MLA

Barell John, . Playgrounds of our minds. New York: Teachers College Press. 1980.