Cita APA

Frei, B., & Head, H. (1989). The Guinness book of answers: The complete reference handbook.

Chicago Edition Citation

Frei, Beatrice, i Honor Head. The Guinness Book of Answers: The Complete Reference Handbook. London, Guinness Publishing, 1989.

Cita MLA

Frei, Beatrice, i Honor Head. The Guinness Book of Answers: The Complete Reference Handbook. 1989.