Cita APA (7th ed.)

Halacy, D. (1968). Century 21 : your life in the year 2001 and: Beyond. Macrae Smith.

Cita Chicago (17th ed.)

Halacy, D.S. Century 21 : Your Life in the Year 2001 and: Beyond. Philadelphia: Macrae Smith, 1968.

Cita MLA (9th ed.)

Halacy, D.S. Century 21 : Your Life in the Year 2001 and: Beyond. Macrae Smith, 1968.

Atenció: Aquestes cites poden no estar 100% correctes.