Παραπομπή APA

Friedrich, P. (1970). Proto-Indo-European trees: Arboreal system of prehistoric people. University of Chicago Press.

Παραπομπή Chicago Style

Friedrich, Paul. Proto-Indo-European Trees: Arboreal System of Prehistoric People. University of Chicago Press, 1970.

Παραπομπή MLA

Friedrich, Paul. Proto-Indo-European Trees: Arboreal System of Prehistoric People. University of Chicago Press, 1970.

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