Gittin 5:7

A person with congenital deafness may communicate with others (in transactions) through gestures; Ben Beseira says he may also use lip reading for transactions involving movable property (which are more lenient than transactions involving real estate). A minor’s purchase is valid and his sale is valid for transactions involving movable property.

Gittin 5:8

The following things were instituted in order to promote peace (darchei shalom): a kohein reads the Torah first, followed by a Levi and then a Yisroel; the inhabitants of a courtyard continue to place the food for their communal eiruv in the house where they are accustomed to do so; the pit that is closest to the body of water is filled first; placing traps to catch wild animals, birds and fish is like stealing. Rabbi Yosi says it’s not just like stealing, it actually is stealing! Taking an object found by a person with congenital deafness, a person lacking mental competence or a minor is like stealing; Rabbi Yosi says that it actually is stealing. If a needy person is beating at the top of an olive tree (to get the portions due to the poor), taking whatever is below him is like stealing; once again, Rabbi Yosi says that it actually is stealing. One must not prevent a non-Jew from gathering gleanings, the corners of a field or forgotten sheaves (the aforementioned portions left for the needy) in order to promote peace.