共 54 条
[1]
Angrist JD, 2009, MOSTLY HARMLESS ECONOMETRICS: AN EMPIRICISTS COMPANION, P1
[6]
Black F., 1976, P 1976 M BUS EC STAT, P177, DOI [DOI 10.1002/FUT.22086, DOI 10.1016/0304-405X(76)90024-6]