CONJUGATE POINTS ALONG NULL GEODESICS IN A CLASS OF SPACETIMES
邝志全, 梁灿彬, 吴月江
CONJUGATE POINTS ALONG NULL GEODESICS IN A CLASS OF SPACETIMES
KUANG ZHI-QUAN (邝志全), LIANG CAN-BIN (梁灿彬), WU YUE-JIANG (吴月江)
中国物理B . 1996, (3): 161 -169 .  DOI: 10.1088/1004-423X/5/3/001