1. Fulton CT: Two-point boundary-value problems with eigenvalue parameter contained in the boundary conditions. Proc. R. Soc. Edinb. 1977, 77: 293-308. 10.1017/S030821050002521X
2. Tikhonov AN, Samarskii AA Dover Books on Physics and Chemistry. In Equations of Mathematical Physics. Dover, New York; 1990.
3. Kapustin NY, Moisseev EI: On a spectral problem with spectral parameter in boundary condition. Differ. Equ. 1997, 33: 115-119.
4. Benedek A, Panzone R: On inverse eigenvalue problem for a second order differential equation with parameter contained in the boundary conditions. Notas Algebra Analysis 1980, 9: 1-13.
5. Mamedov SG: Determination of a second order differential equation with respect to two spectra with a spectral parameter entering into the boundary conditions (Russian). Izv. Akad. Nauk Azerb. SSR, Ser. Fiz.-Tekh. Mat. Nauk 1982, 3: 15-22.