共 34 条
[13]
HUNTER AS, 1961, 57 OR AGR EXPT STA T
[15]
LUTZ JA, 1962, 543 VIRG AGR EXPT ST
[16]
MORGAN A., 1949, JOUR DEPT AGRIC VICTORIA, V47, P199
[19]
OLSEN S. R., 1962, SOIL SCI SOC AMER PROC, V26, P222
[20]
PETERSON HB, 1953, USDA927 CIRC