Citação norma APA
(1990). Year Book. The 1990 World Book: A Review of the Events of 1989.The Annual Supplement to The World Book Encyclopedia. The World Book,Inc.
Citação norma Chicago
Year Book. The 1990 World Book: A Review of the Events of 1989.The Annual Supplement to The World Book Encyclopedia. Chicago: The World Book,Inc, 1990.
Citação norma MLA
Year Book. The 1990 World Book: A Review of the Events of 1989.The Annual Supplement to The World Book Encyclopedia. The World Book,Inc, 1990.
Nota: a formatação da citação pode não corresponder 100% ao definido pela respectiva norma.