Niovi Kehayopulu, George Lepouras and Michael Tsingelis
Math. Japonica 46, No. 2 (1997), 311-315. Îœathematical Reviews: 06019 (Alexey Vernitskii). Zentralblatt fur Math 890.06009 (H. Mitsch).
Math. Japonica 46, No. 2 (1997), 311-315. Îœathematical Reviews: 06019 (Alexey Vernitskii). Zentralblatt fur Math 890.06009 (H. Mitsch).