Reference for Eruvin 41:8

בורגנין בבבל לא דשכיחי בידקי פסי ביראות בחו"ל לא דלא שכיחי מתיבתא אבל איפכא עבדינן

Others say that R'Jeremiah B'Abba laid this down in the name of Rab: [The laws of] isolated huts and strips [of wood] around wells are not [applicable] either to Babylon or to other countries outside the Land of Israel. [The law of] isolated huts [is inapplicable] to Babylon because the bursting of dams is of frequent occurrence. In other countries outside the Land of Israel also it is not [applicable] because there thieves<span class="x" onmousemove="('comment',' Who steal the huts.');">¹⁵</span>

Jastrow