Gaya APA

Swanson, C, P., Dixon, D. (NULL). Encyclopedia of science the earth our planet its land, sea and air . New: New York: Macmillan Pub.Co.; 1991.

Gaya MLA

Swanson, Carl, P.., Dixon, Dougal. "Encyclopedia of science the earth our planet its land, sea and air". New: New York: Macmillan Pub.Co.; 1991, NULL. Text.