At the beginning of the siddur appears his approbation, where he writes: “Said Ephraim… it is from my hand that this siddur, with the commentary of the Ra’avan, has come to print.” Later, he requests that the siddur not be reprinted without his permission, in accordance with accepted practice. Rabbi Shemaria of Hrymailiv, a disciple of Rabbi Ephraim Zalman Margulies, also refers in his work Iyun Tefillah to the “siddur printed with the commentary of the Ra’avan, of blessed memory, which my teacher printed in Ostroh…”  | Read More The Yeshiva World