APA

Daniken E. V., Heron M., . (1980). Signs of the Gods?. New York: G. P. Putnan's.

Chicago

Daniken Erich Von, Heron Michael, . 1980. Signs of the Gods?. New York: G. P. Putnan's.

Harvard

Daniken E. V., Heron M., . (1980). Signs of the Gods?. New York: G. P. Putnan's.

MLA

Daniken Erich Von, Heron Michael, . Signs of the Gods?. New York: G. P. Putnan's. 1980.