共 17 条
[2]
BAUER A, 1969, 23 N DAK STAT U RES
[3]
CHILCOTT EC, 1931, USDA81 MISC CIR
[4]
COLE JS, 1933, USDA1004 B
[5]
HAAS HJ, 1976, ARSNC38 USDA
[6]
HAAS HJ, 1957, USDA1164 TECH B
[7]
HARPER HJ, 1959, B531 OKL STAT U AGR
[9]
MATHEWS OR, 1923, USDA1139 B
[10]
MICHALYNA W., 1961, CANADIAN JOUR SOIL SCI, V41, P5