Reference for Shevuot 92:6
נחבל כיצד: אמר רב יהודה אמר שמואל לא שנו אלא במקום שיכול לחבל בעצמו אבל במקום שאינו יכול לחבל בעצמו נוטל שלא בשבועה
HE WHO WAS WOUNDED,' - HOW? Rab Judah said that Samuel said: They did not teach it,<span class="x" onmousemove="('comment',' In the Mishnah that the injured person takes an oath that the other had inflicted upon him the wound which he exhibits.');"><sup>19</sup></span> except [if the wound were] in a spot where he could have inflicted it himself,<span class="x" onmousemove="('comment',' Therefore an oath is necessary that the other did it.');"><sup>20</sup></span> but if it is in a spot where he could not have inflicted it himself, he receives [compensation] without an oath.<span class="x" onmousemove="('comment',' For witnesses testified that he entered the other's premises whole, and came out injured.');"><sup>21</sup></span>