Pečiulytė S, Štikonienė O, Štikonas A. Investigation of Negative Critical Points of the Characteristic Function for Problems with Nonlocal Boundary Conditions. NAMC [Internet]. 2008 Oct. 20 [cited 2024 May 5];13(4):467-90. Available from: https://www.journals.vu.lt/nonlinear-analysis/article/view/14552