Cita APA (7th ed.)

SALES, R. [. (1978). Children's Britannica 9: Helen of troy - ivy. Encyclopaedia Britannica International.

Cita Chicago (17th ed.)

SALES, Robin [Ed.]. Children's Britannica 9: Helen of Troy - Ivy. London: Encyclopaedia Britannica International, 1978.

Cita MLA (9th ed.)

SALES, Robin [Ed.]. Children's Britannica 9: Helen of Troy - Ivy. Encyclopaedia Britannica International, 1978.