De Camp, L. S. (1961). The heroic age of American invention. Garden City, N.Y: Doubleday.
Čikaški stil citiranjaDe Camp, L. Sprague. The Heroic Age of American Invention. Garden City, N.Y: Doubleday, 1961.
MLA način citiranjaDe Camp, L. Sprague. The Heroic Age of American Invention. Garden City, N.Y: Doubleday, 1961.
Upozorenje: Ovi citati možda nisu uvijek 100% točni.