(1989). Yearbook of science and the future 1990. Encyclopaedia Britannica.
Cita Chicago Style (17a ed.)Yearbook of Science and the Future 1990. Chicago [etc.]: Encyclopaedia Britannica, 1989.
Cita MLA (9a ed.)Yearbook of Science and the Future 1990. Encyclopaedia Britannica, 1989.
Precaución: Estas citas no son 100% exactas.