Gaya APA

Gould, E, J, L, G, ;, C, G. (1989). Life at the edge: readings from scientific American magazine . New York: W. H. Freeman and Company.

Gaya MLA

Gould, Ed., James, L., Gould, ;, Carol, Grant. "Life at the edge: readings from scientific American magazine". New York: W. H. Freeman and Company, 1989. Text.