%0 Journal Article %A V. M. Babich %T High-frequency point source of oscillation in a~neighbourhood of a~concave mirror %J Zapiski Nauchnykh Seminarov POMI %D 1975 %P 5-19 %V 51 %I mathdoc %U http://geodesic.mathdoc.fr/item/ZNSL_1975_51_a0/ %G ru %F ZNSL_1975_51_a0