Zeros of the Green's function for the de la Vallee-Poussin problem

The Green's function for the de la Vallee-Poussin problem Lx≡x(n)+p1(t)x(n-1)+...+pn(t)x=f; x(ai)=Ai(0), x'(ai)=Ai(1),...,x(ν1-1)(ai)=Ai(ν1-1), i=1,...,m, where a=a1=2, Σνi=n, pi(.) and f(.) element of L1[a,b] is investigated. It is defined in the square a<=t,s<=b, and vanishes at the lines t=ai, i=1,...,m, s=b; it is proved that the orders of its zeros have uniform bounds. Bibliography: 27 titles