Rabbi Moshe Feinstein (1895-1986) became the leading halachic authority of his generation, and his p’sakim (halachic rulings) were accepted worldwide. Rav Moshe Feinstein's halachic decisions have been published in this collection called Igros Moshe (The Letters of Moshe).
See also : Yad Moshe - An Index for Igrot Moshe
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