Gaya APA

Swanson, C, P., Twist, C. (NULL). Encyclopedia of science 7 the environment ecology, pollution and agriculture . New: New York: Macmillan Pub.Co.; 1991.

Gaya MLA

Swanson, Carl, P.., Twist, Clint. "Encyclopedia of science 7 the environment ecology, pollution and agriculture". New: New York: Macmillan Pub.Co.; 1991, NULL. Text.