Sheldon, S. (2001). The sky is falling. Compass Press, HarperCollins Publishers.
Chicago-viite (17. p.)Sheldon, Sidney. The Sky Is Falling. London ; Oxford ; Melbourne: Compass Press, HarperCollins Publishers, 2001.
MLA-viite (8. p.)Sheldon, Sidney. The Sky Is Falling. Compass Press, HarperCollins Publishers, 2001.
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