Friedrich, P. (1970). Proto-Indo-European trees: Arboreal system of prehistoric people. University of Chicago Press.
استشهاد بنمط شيكاغوFriedrich, Paul. Proto-Indo-European Trees: Arboreal System of Prehistoric People. University of Chicago Press, 1970.
MLA استشهادFriedrich, Paul. Proto-Indo-European Trees: Arboreal System of Prehistoric People. University of Chicago Press, 1970.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.