Reference for Yevamot 31:17
רבי יוחנן וסביא דאמרי תרוייהו אין מקבלים גרים מן התרמודים ומי אמר ר' יוחנן הכי והתנן כל הכתמים הבאים מן הרקם טהורים
Others say: Rami b. Ezekiel learnt, 'No proselytes are to be accepted from the Kartuenians'. Are not Kartuenians the same as Cordyenians? — R. Ashi replied: No; Kartuenians are a class by themselves, and Cordyenians are a class by themselves, as people, in fact, speak of 'disqualified Kartuenians'.<span class="x" onmousemove="('comment',' The Cordyenians, however, are not tainted. ');"><sup>30</sup></span> Both R. Johanan and Sabya maintain that no proselytes may be accepted from the Tarmodites. Did R. Johanan. however, say such a thing? Surely we learned: All blood stains [on women's garments] that come from Rekem<span class="x" onmousemove="('comment',' Place on the borders of Palestine. Perhaps Petra or the Biblical Sela in Edom, v. Git., Sonc. ed. p. 1, n. 2. ');"><sup>31</sup></span>