APA

Mayer M., Twentieth Century Fund, . (1968). Diploma: international schools and university entrance. New York: Twentieth Century Fund.

Chicago

Mayer Martin, Twentieth Century Fund, . 1968. Diploma: international schools and university entrance. New York: Twentieth Century Fund.

Harvard

Mayer M., Twentieth Century Fund, . (1968). Diploma: international schools and university entrance. New York: Twentieth Century Fund.

MLA

Mayer Martin, Twentieth Century Fund, . Diploma: international schools and university entrance. New York: Twentieth Century Fund. 1968.