Acikgoz M., Araci S., & ŞenE. (2016). Spectral problem for Sturm – Liouville operator with retarded argument which contains a spectral parameter in boundary condition. Ukrains’kyi Matematychnyi Zhurnal, 68(8), 1102-1114. Retrieved from https://umj.imath.kiev.ua/index.php/umj/article/view/1905