“…For example, some boundary-value problems with transmission condition arise in heat and mass transfer problems (see, e.g., [40]), in vibrating-string problems where the string is additionally loaded by point masses (see, e.g., [37]), and in diffraction problems (see, e.g., [39]). Moreover, some problems with boundary conditions depending on a spectral parameter occur in the theory of small vibrations of a damped string and in the problem of freezing of a liquid (see, e.g., [36][37][38]).…”