Reference for Yoma 22:9

אלא ביתך למה לי כדרבא דאמר רבא דרך ביאתך וכי עקר איניש כרעיה דימינא עקר ברישא

it is considered nothing;<span class="x" onmousemove="('comment',' And requires no mezuzah, for the minimum for any doorway is ten in height for the whole doorway, four in width, three for the posts; below it is but 'solid' earth.');">¹²</span> again, if the post is three handbreadths in height, but the [whole] doorway not even ten,it is also considered nothing.<span class="x" onmousemove="('comment',' And requires no mezuzah, for the minimum for any doorway is ten in height for the whole doorway, four in width, three for the posts; below it is but 'solid' earth.');">¹²</span>

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