Responsa for Eruvin 176:9

אלא לאו ש"מ דר"א בן יעקב היא ש"מ

to R'Eliezer B'Jacob?<span class="x" onmousemove="('comment',' An individual. Sc. why could not R. Zera adopt Rabbah's explanation which would have enabled him to escape this difficulty?');">²¹</span> - Raba replied: Our Mishnah presented to him a difficulty: What was the object of stating, IF THE AREA OF A COURTYARD WAS less<span class="x" onmousemove="('comment',' Cf. MS.M. The following three words are wanting in cur. edd.');">²²</span> THAN FOUR CUBITS<span class="x" onmousemove="('comment',' Which implies that if the total area was four cubits by four it matters little whether each side was four cubits long or whether the courtyard was long and narrow, two of its sides being shorter, and two longer than four cubits.');">²³</span>

Teshuvot Maharam