(1)
Čiupaila, R.; Jesevičiūtė, Ž.; Sapagovas, M. On the Eigenvalue Problem for One-Dimensional Differential Operator With Nonlocal Integral Condition. NAMC 2004, 9 (2), 109-116. https://doi.org/10.15388/NA.2004.9.2.15159.