共 15 条
[1]
AGARWAL RP, 1991, ANN POL MATH, V52, P211
[7]
KALINOWSKI J, 1974, ANN POL MATH, V30, P71
[8]
LAZER AC, 1991, P AM MATH SOC, V3, P721
[10]
NACHMAN A, 1980, SIAM J APPL MATH, P275