  In three-dimensional case, we consider two classical operators: Schrodinger
operator and an operator in the divergence form. For slowly-decaying
oscillating potentials, we establish spatial asymptotics of the Green's
function. The main term in this asymptotics involves vector-valued analytic
function whose behavior is studied away from the spectrum. The absolute
continuity of the spectrum is established as a corollary. For the operator in
the divergence form, we consider the wave equation and establish existence of
wave operators.
