APA aipamena

Robert Ludlum & Gayle Lynds. (2000). The heads factor. Harper Collins.

Chicago Style aipamena

Robert Ludlum and Gayle Lynds. The Heads Factor. London: Harper Collins, 2000.

MLA aipamena

Robert Ludlum and Gayle Lynds. The Heads Factor. Harper Collins, 2000.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.