Ryan, P. J. Euclidean and non-Euclidean geometry: an analytical approach/ Patrick J. Ryan. - Cambridge, UK New York: Cambridge University Press, 1986. - xvii, 215 p.: ill.; 24 cm. Includes index. Bibliography: p. 210-211. ISBN: 0521256542 0521276357 (pbk.) LCCN: 85017146 Nat. Bib. No.: GB85-38940 Subjects--Topical Terms: Geometry, Plane.Geometry, Non-Euclidean. Dewey Class. No.: 516.1 / R989e Universal Decimal Class. No.: 513 514.13