Reference for Shabbat 15:3

רבא אמר אפי' אינה רחבה ו' פטור מ"ט אי אפשר לקרומיות של קנה שלא יעלו למעלה מעשרה

into the street, [even] if it is ten [handbreadths] high but not six broad, he is liable; if six broad, he is exempt.<span class="x" onmousemove="('comment',' A circle with a diameter of six is the least (roughly) in which a square of four can be inscribed. Now, as stated above (6a), an object four square is a separate domain itself, and no liability is incurred for throwing one domain into another. ');">³</span>

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