APA

Rumbelow D., . (1971). I spy blue. London: MaCmillan.

Chicago

Rumbelow Donald, . 1971. I spy blue. London: MaCmillan.

Harvard

Rumbelow D., . (1971). I spy blue. London: MaCmillan.

MLA

Rumbelow Donald, . I spy blue. London: MaCmillan. 1971.