Koch, R. (1955). The book of signs: Which contains all manner of symbols used from the earliest times to the Middle Ages by primitive peoples and early Christians. New York: Dover Publications.
Παραπομπή Chicago StyleKoch, Rudolf. The Book of Signs: Which Contains All Manner of Symbols Used From the Earliest Times to the Middle Ages By Primitive Peoples and Early Christians. New York: Dover Publications, 1955.
Παραπομπή MLAKoch, Rudolf. The Book of Signs: Which Contains All Manner of Symbols Used From the Earliest Times to the Middle Ages By Primitive Peoples and Early Christians. New York: Dover Publications, 1955.
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