%0 Journal Article %A Valery Dryuma %T Four-dimensional Ricci-flat space defined by the KP-equation %J Buletinul Academiei de Ştiinţe a Republicii Moldova. Matematica %D 2008 %P 108-111 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/BASM_2008_3_a11/ %G en %F BASM_2008_3_a11