共 20 条
[1]
Andersson S., 1972, Grundforbattring, V2-3, P53
[3]
BREMNER J. M., 1958, JOUR AGRIC SCI, V51, P40
[4]
Bremner JM., 1965, ISOTOPE RATIO ANAL N
[7]
FOCHT D D, 1978, P433
[10]
KLEMEDTSSON L, 1977, SWED J AGR RES, V7, P179