Reference for Bava Metzia 107:4

איבעיא להו חומש מעכב או אינו מעכב ד' בד' פריק ואכנפשיה מוסיף חומש אלמא חומש לא מעכב או דלמא ארבעה בחמשה פריק וחומש מעכב

The scholars propounded: Does the fifth restrain or not?<span class="x" onmousemove="('comment',' If one redeems the second tithe without adding a fifth, does this omission restrain him from eating that produce outside Jerusalem, it being regarded as unredeemed, or not? ');">⁵</span> [Thus:] do four [<i>zuz</i>] redeem four [<i>zuz</i>'s worth of second tithes], whilst a fifth is independently added,<span class="x" onmousemove="('comment',' But not as part of the actual redemption. ');">⁶</span>

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