Kushner, Alexei. Contact geometry and non-linear differential equations / Alexei Kushner, Valentin Lychagin and Vladimir Rubtsov. - Cambridge, UK ; New York : Cambridge University Press, 2007. - xxi, 496 p. : ill. ; ISBN: 0521824761 (hbk.) 9780521824767 (hbk.) Subjects--Topical Terms: Contact manifolds.Differential equations, Nonlinear. Universal Decimal Class. No.: 517.957 / KUS