About generalized resolvent of one integro-diferential operator of the second order on semiaxis

In this article a symmetrical integro-differential operator of the second order on semiaxis is considered. Its quasiselfadjoint extension is described, and the formula for all generalized resolvents of this operator in $L^2(0,+\infty)$ is constructed. It also prooves that any generalized resolvent $R_\lambda$ is an integral operator for any nonreal $\lambda$.