Reference for Bava Metzia 32:15

א"ר אבהו א"ר יוחנן המוצא שטר חוב בשוק אע"פ שכתוב בו הנפק לא יחזירו לבעלים

which [documents] are not concerned with repayment. Raba [then] said: And are not such [documents] concerned with repayment? Have not the Nehardeans<span class="x" onmousemove="('comment',' A famous town in Babylonia, near the junction of the Euphrates and 'Nahr Malka,' and the seat of the Academy rendered famous by Samuel and other great Rabbis. Among the natives of Nehardea was R. Nahman (v. Hul. 95b). ');">¹⁵</span>

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