Reference for Eruvin 38:9
ארי"ך יות"ר בת"ל חיצ"ת חצ"ר שיבש"ה סימן: בעא מיניה אביי מרבה האריך בדיומדין כשיעור פשוטין לר"מ מהו
Extended more in a mound fence of a courtyard that dried up) Abaye enquired of Rabbah: What is the ruling according to R'Meir where one extended the corner-piece [so that the excess of their width<span class="x" onmousemove="('comment',' Above that of one cubit in extent at the extremities of each side of the well enclosure.');"><sup>20</sup></span> was] equal to the required width of the single boards?<span class="x" onmousemove="('comment',' Is the reduction of the gaps to ten cubits in this manner effective, or is it necessary, once a gap was wider than the permitted ten cubits, to reduce it by the fixing of two special boards on each side of the enclosure and at the same distance from each corner-piece so that the additional single boards might be distinguishable?');"><sup>21</sup></span>