This paper discusses the quasilinearization process, that is,
reduction of a given boundary value problem to a quasi-linear one.
Quasi-linear BVP has a solution of definite type which is induced
by oscillatory properties of the linear part of a system.
Conditions are given for a solution of a modified (quasi-linear)
BVP to satisfy also the original problem. It is shown that
multiple quasilinearizations with different linear parts if
possible lead to multiple solutions.