APA-referens (7:e uppl.)

Sullivan, W. (1966). We are not alone: The search for intelligent life on other worlds (Rev. ed.). New American Library.

Chicago-referens (17:e uppl.)

Sullivan, Walter. We Are Not Alone: The Search for Intelligent Life on Other Worlds. Rev. ed. New York: New American Library, 1966.

MLA-referens (9:e uppl.)

Sullivan, Walter. We Are Not Alone: The Search for Intelligent Life on Other Worlds. Rev. ed. New American Library, 1966.