%0 Journal Article %A V. P. Derevenskii %T Hyperbolic functions and first-order nonlinear ordinary differential equations over a Banach algebra %J Izvestiâ vysših učebnyh zavedenij. Matematika %D 2006 %P 7-18 %N 8 %I mathdoc %U http://geodesic.mathdoc.fr/item/IVM_2006_8_a1/ %G ru %F IVM_2006_8_a1