“…where A, B, C, D are unknowns, which should be determined from boundary conditions (15), (17), (19) and (20). Satisfying these boundary conditions by " h I ðn; zÞ given in (28) and " h II ðn; zÞ given in (29) we obtain four linear algebraic equations for unknowns A, B, C, D and the solution takes the form…”