-. (1983). Grolier academic encyclopedi 18. Grolier Internasional.
Chicago Style (17th ed.) Citation-. Grolier Academic Encyclopedi 18. (sl): Grolier Internasional, 1983.
MLA (9th ed.) Citation-. Grolier Academic Encyclopedi 18. Grolier Internasional, 1983.
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