%0 Journal Article %A Jian Zhang %A Ji Shu %T On a Class of Nonlinear Schrödinger Equations with Nonnegative Potentials in Two Space Dimensions %J Matematičeskie zametki %D 2012 %P 515-521 %V 91 %N 4 %U http://geodesic.mathdoc.fr/item/MZM_2012_91_4_a3/ %G ru %F MZM_2012_91_4_a3