The Issur of Shaving the Pe'ot, 12 Seifim: There are two pe'ot/corners of the head. [Where the] head ends is where it joins with the jaw, on the right and on the left.
The person whose pe'ot are shaved off is also liable if he assists in shaving, leaning his head to him so that he shaves his pe'ah, but there is prohibition even if he does not help, therefore it is forbidden to have one's pe'ot shaved off even by means of an idolater.
One who rounds [the head of] a minor male is liable. (But it is permitted to round [the head of] an idolater or a woman -- Beit Yosef, in the name of the RoSh). But there are those who have doubt regarding this (Beit Yosef in the name of י"א). A minor is permitted to be rounded by an idolater (Ran, in the perek Eilu Hen Hagolin).