Hobson, E. W.
A Treatise on Plane and Advanced Trigonometry. 7th. edn. - Mineola; New York Dover Publications 2005 - xv, 383p. - Dover Phoenix Editions .
978-0-486-44177-1
A Treatise on Plane and Advanced Trigonometry. 7th. edn. - Mineola; New York Dover Publications 2005 - xv, 383p. - Dover Phoenix Editions .
978-0-486-44177-1