Christie, A. <. (1984). Death in the air = Tod in den Wolken <engl.>: Agatha Christie. Berkley Books.
Cita Chicago (17th ed.)Christie, Agatha <1890-1976>. Death in the Air = Tod in Den Wolken <engl.>: Agatha Christie. New York: Berkley Books, 1984.
Cita MLA (8th ed.)Christie, Agatha <1890-1976>. Death in the Air = Tod in Den Wolken <engl.>: Agatha Christie. Berkley Books, 1984.
Atenció: Aquestes cites poden no estar 100% correctes.