共 29 条
[1]
ADAMS JD, 2000, 7484 NBER
[5]
BRANSTETTER L, 1999, INT C ROL TECHN TRAN
[6]
Chamberlain G., 1984, HDB ECONOMETRICS, V2, P1247, DOI DOI 10.1016/S1573-4412(84)02014-6
[7]
CHU W, 2000, C NAT E AS EXP AC SI
[8]
COCKBURN I, 1988, AM ECON REV, V78, P419
[9]
CUNEO P, 1984, R D PATENTS PRODUCTI
[10]
Fuss M., 1978, PRODUCTION EC DUAL A, VI