Reference for Kiddushin 156:4
רבי יהודה אומר מן המשיאים לכהונה יקחו רבי יהודה לטעמיה דאמר בת גר זכר כבת חלל זכר כל שאתה נושא בתו אתה נושא אלמנתו וכל שאי אתה נושא בתו אי אתה נושא אלמנתו
of a priest they shall take': [i.e.,] those of the other priests may take. R'Judah interpreted: of those who ca give [their daughters] in marriage to the priesthood they may take.<span class="x" onmousemove="('comment',' I.e., they may take the widow of a man whose daughter was fit for the priesthood, thus excluding the widow of a proselyte.');"><sup>7</sup></span> R'Judah is in harmony with his view, for he said: THE DAUGHTER OF A MALE PROSELYTE IS AS THE DAUGHTER OF A MALE HALAL: when you may marry his daughter, you may marry his widow; and when you may not marry his daughter, you may not marry his widow.<span class="x" onmousemove="('comment',' V. supra 75a.');"><sup>8</sup></span>