On the "movement" of the zeros of eigenfunctions of the Sturm-Liouville   problem
  We study the dependence of the zeros of eigenfunctions of Sturm-Liouville problem on the parameters that define the boundary conditions. As a corollary, we obtain Sturm oscillation theorem, which states that the $n$-th eigenfunction has $n$ zeros. 
Tigran Harutyunyan, Avetik Pahlevanyan, Yuri Ashrafyan
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