Bayis Malei Sefarim:
It is a Mitzvah to publish [and purchase] Chumashim, Mishnah, Gemara and their commentaries. Some Poskim rule that this Mitzvah is a positive Biblical command, and is in place of the Mitzvah of purchasing a Sefer Torah. [This Mitzvah is fulfilled through writing or purchasing all Torah Sefarim and not just those listed above. One is especially to purchase Sefarim dealing with practical Halacha which will be studied frequently in order to know what one is to practically follow. Likewise every child is to have a Siddur, Chumash and Tehillim of his own [Chitas]. These Sefarim are to be placed in his room. One is likewise to donate Sefarim to public libraries and help them expand. Every home is to likewise contain the following three Sefarim: Keser Shem Tov of the Baal Shem Tov, Or Torah of the Maggid and Tanya. ]
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 Michaber 270/2
 Shach 270/5; Perisha 270
Other Poskim: Many Poskim rule that the Mitzvah of purchasing SZefarim is not included in the Mitzvah of writing a Sefer Torah, and rather this Mitzvah is intact even today. [Michaber 270/1; Levush; Magid Mishneh brought in Shach ibid]
 Sichas Hei Teves 1988 printed in Hisvadyus 2/170-173
 Sichas 1950 p. 265; Sefer Haminhagim