%0 Journal Article %A T. S. Todorov %T On a Class of Nelson-Type Examples for Higher Order Partial Differential Operators %J Mathematica balkanica %D 1996 %P 373 %V 10 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/MABA_1996_10_4_a6/ %F MABA_1996_10_4_a6