A generalization of a theorem of Tikhonov (Q1821936)

The paper contains a generalization of the well-known result of A. N. Tikhonov on the possibility of construction of asymptotics to the solution of the Cauchy problem for the system of differential equations with a small parameter \[ dx/d\tau =X(z,x,\tau),\quad \epsilon dz/d\tau =Z(z,x,\tau) \] to a more general system \[ dx/d\tau =X(\tau /\epsilon,z,x,\tau),\quad \epsilon dz/d\tau =Z(\tau /\epsilon,z,x,\tau). \]