Reference for Eruvin 98:8

עגולות דברי ר' חנינא בן אנטיגנוס וחכמים אומרים מרובעות כטבלא מרובעת כדי שיהיה נשכר לזויות

IF, HOWEVER, HE SAID, LET MY SABBATH BASE BE AT ITS ROOT',<span class="x" onmousemove="('comment',' I.e., he specified a particular spot of the size of four cubits under the tree.');">¹⁴</span> HE MAY WALK FROM THE PLACE WHERE HE STANDS TO ITS ROOT A DISTANCE OF TWO THOUSAND CUBITS, AND FROM ITS ROOT TO HIS HOUSE ANOTHER TWO THOUSAND CUBITS.

Jastrow