共 12 条
[3]
CRAMPTON D, 1978, ASTRON ASTROPHYS, V66, P1
[5]
GELDZAHLER BJ, 1980, ASTRON ASTROPHYS, V84, P237
[7]
GREGORY PC, 1980, NATURE
[8]
RAGHAVARAO R, 1965, MNRAS, V129, P159