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This is an edition of an Arabic treatise composed by the eminent Iranian astronomer and mathematician ‘Abd al-Rahm?n al-S?f? (d. 376 A.H./986 C.E.), mostly known for his famous book Suwar al kaw?kib (“ The constellations”).
Entitled Ris?la f? ‘amal al-ashk?l aI-mutas?wiyat al-adl?’ Kullah? bi fathat w?hida (“Treatise on the construction of regular polygons by [compasses of] fixed opening”), it was written on the request of the local ruler ‘Adad al-Dawla Deilami. The present edition has been made using two mss. extant in the Holy Shrine library (Mashhad,
IRAN): MS 5535 (copied in 1286 A.H.) and MS 12121 (copied in 1308 A.H.), both copied from a ms. dated 688 A.H. copied in Maragha. The first ms. has been the basis of our work. Addition for reconstruction of the text, including those taken from the second ms. are given in brackets: [ ].