An elliptic equation of order 2m with general nonlocal boundary-value
conditions, in a plane bounded domain G with piecewise smooth boundary, is
considered. Generalized solutions belonging to the Sobolev space W2m(G) are
studied. The Fredholm property of the unbounded operator corresponding to the
elliptic equation, acting on L2(G), and defined for functions from the space
W2m(G) that satisfy homogeneous nonlocal conditions is proved.Comment: 18 pages, 2 figure