Several Acharonim (e.g. Pnei Yeshoshua to Brachos 15b) write that words of Torah must be enunciated during study.
Which Rishonim agree to this view. (I am asking specifically about those who hold that it is an integral component of the mitzva, not those who encourage it for side reasons such as its characteristic of facilitating memorization.)
I am looking specifically for views that can compellingly ascribed to Rishonim; not just Acharonim who can be found claiming that their views match those of Rishonim.