Key points are not available for this paper at this time.
Let be a domain of Rⁿ with n 2 and p () be a local Lipschitz funcion in with 11 and Up (x) 0 and C 1 are independent of u. These extend the related results obtaind by Adamowicz-H\"ast\"o AH2010 when n=2 and =0.
Wang et al. (Wed,) studied this question.