Sichot Avodat Levi 40:13ืฉืืืืช ืขืืืืช ืืื ืืณ:ืืดื
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Havot Yair 143:4ืืืืช ืืืืจ ืงืืดื:ืืณ
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HaMiddot leCheker haHalakhah, Part I, Method V 10:1ืืืืืืช ืืืงืจ ืืืืื, ืืืง ื, ื; ืฉืชื ืกืืืช ืืืชื ืืืืช ืื ืืื ืืณ:ืืณ
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