Reference for Bava Kamma 194:4

אלא כי אמר שמואל כשמלכיות מקפידות זו על זו היכי מצי ממטי להו דממטי לה ע"י הדחק דלא בחשי ואי משכחי קפדי

Now, does this not imply that if the coins were of the later kings, even though analogous [in one respect] to coins of the earlier kings,<span class="x" onmousemove="('comment',' Such as where they were declared obsolete in a particular province. ');">⁷</span> it would be possible to effect the redemption by means of them?<span class="x" onmousemove="('comment',' Even where one had not occasion to go there, which refutes R. Nahman's view. ');">⁸</span>

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