“…Bae and Choe [4], Bae and Jin [5][6][7][8][9], Brandolese [10,11], Brandolese and Vigneron [12], Fujigaki and Miyakawa [14] and Schonbek [20][21][22] considered the asymptotic behaviour for weak and strong solutions of (1.1), and many important and interesting results were obtained. Bae and Choe [4], Bae and Jin [5][6][7][8][9], Brandolese [10,11], Brandolese and Vigneron [12], Fujigaki and Miyakawa [14] and Schonbek [20][21][22] considered the asymptotic behaviour for weak and strong solutions of (1.1), and many important and interesting results were obtained.…”