Reference for Bava Batra 324:1

איבעיא להו שיטה ומחצה מאי תא שמע הרחיק את העדים שני שיטין פסול הא שיטה ומחצה כשר

The question was raised: What [is the ruling in the case of] a line and a half?<span class="x" onmousemove="('comment',' If a space sufficient for the writing of a line and a half was left between the text and the witnesses' signatures. ');">¹</span> — Come and hear: 'If the [signatures of the] witnesses were removed two lines from the text,<span class="x" onmousemove="('comment',' Cf. BaH, a.l. ');">²</span>

Jastrow