Bull. Korean Math. Soc. 2001; 38(1): 121-128
Printed March 1, 2001
Copyright © The Korean Mathematical Society.
Sang-Cho Chung and Hyoung June Ko
Chungnam National University, Yonsei University
2011; 48(1): 95-104
© 2022. The Korean Mathematical Society. Powered by INFOrang Co., Ltd