共 8 条
[1]
BISWELL H. H., 1957, JOUR FOREST, V55, P372
[4]
FETH JH, 1964, 1535I US GEOL SURV W, pI1
[5]
FRIEDRICH CA, 1955, YEARBOOK AGRICULTURE, P185
[6]
GORHAM E, 1961, GEOL SOC AM BULL, V72, P795
[7]
JOHNSON CM, 1959, 766 CAL AGR EXP STN, P27
[8]
ROBERSON CE, 1963, 475C US GEOL SURV PR, pC212