APA

Strughold H., . (1971). Your body clock. New York: Scribner.

Chicago

Strughold Hubertus, . 1971. Your body clock. New York: Scribner.

Harvard

Strughold H., . (1971). Your body clock. New York: Scribner.

MLA

Strughold Hubertus, . Your body clock. New York: Scribner. 1971.