In this paper,the following result is given by using Hodge decomposition:There exists r0 = r0(n, p, a, b),such that if u 2 W1,rloc () is a very weak solution of (1.1),withmax{1, p−1} < r < p and u 2 W1,r0 (; @\E), where E @ is a closed set and small inan appropriate capacity sense, then u = 0, a.e. in provided that r0 < r < p.
