Reference for Arakhin 64:3

רבא אמר

Raba said: Gamala in Galilee [is mentioned so as] to exclude [any city called] Gamala in other countries; Gadud in Transjordania to exclude Gadud in any other countries; but with regard to the others, since there are none of the same name [like them], no [statement as to their location] was necessary.

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