Reference for Bava Kamma 225:6

רב אסי איקלע בי רב כהנא חזא ההיא איתתא דאזמנה לדינא בפניא ובצפרא כתיב עלה פתיחא א"ל לא סבר לה מר להא דאמר רב חסדא קובעין זמן שני וחמישי ושני

or during Tishri,<span class="x" onmousemove="('comment',' On account of urgent agricultural work; cf. Ber. 35b. ');">⁵</span> or on the eve of a holy day or on the eve of a Sabbath. We can, however, during Nisan cite him to appear after Nisan, and so also during Tishri we may cite him to appear after Tishri, but on the eve of the Sabbath we do not cite him to appear after Sabbath, the reason being that he might be busy<span class="x" onmousemove="('comment',' And take no notice of the summons. ');">⁶</span>

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