Ward, D. C. (2014). Call waiting. Carcanet.
Chicago Style (17th ed.) ZitazioaWard, David C. Call Waiting. Manchester, England: Carcanet, 2014.
MLA (9th ed.) ZitazioaWard, David C. Call Waiting. Carcanet, 2014.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.