共 5 条
[1]
GRONAU R, 1973, J POLIT ECON, V81, P168
[2]
HIRSCHLIEFER J, 1960, WATER SUPPLY EC TECH, P44
[3]
PETERSON RD, 1978, AM J EC SOCIOLOG APR, P145
[4]
Walker KE., 1969, J HOME EC, V61, P621
[5]
[No title captured]