On the nature of solutions of the linear homogeneous fourth order differential equation

This work is a study of the classical linear homogeneous differential equation (L) = p(t)y" + q(t)y' + r(t)y. The following properties of solutions of (L) are considered: (a) boundedness (h) asymptotic behavior (c) behavior for large t values (d) behavior of solutions possessing multiple zeros (e) disconjugacy (f) distribution of zeros. A sufficient condition for disconjugacy of (L) is given, and conditions are stated which guarantee the existence of three linearly independent uniformly bounded solutions whose first three derivatives tend to zero.