הלכה על מנחות 59:10

For everyone to write a Torah scroll for himself: That we were commanded that each man in Israel must have a Torah scroll (Sefer HaMitzvot LaRambam, Mitzvot Ase 18). If he wrote it with his [own] hand, this is praiseworthy and very dear; and as they, may their memory be blessed, said (Menachot 30a), "If he wrote it" - meaning to say, with his hand - "Scripture attributes [it] to him as if he received it from Mount Sinai." But one who is unable to write with his hand must pay someone to write it for him. And about this it is stated (Deuteronomy 31:19), "And now, write for yourselves this poem and teach it to the Children of Israel" - meaning to say, write for yourselves Torah, which contains this poem.