Cita APA (7th ed.)
Christie, A. (2006). Agatha christie 1920s omnibus. Harper Collins Pub.
Cita Chicago (17th ed.)
Christie, Agatha. Agatha Christie 1920s Omnibus. London: Harper Collins Pub, 2006.
Cita MLA (9th ed.)
Christie, Agatha. Agatha Christie 1920s Omnibus. Harper Collins Pub, 2006.
Atenció: Aquestes cites poden no estar 100% correctes.