共 16 条
- [2] ALTSCHULER ZS, 1959, US GEOL SURVEY PROFE, VD314, P45
- [3] DAVIDSON CF, 1952, 124 GEOL SURV MUS AT
- [4] HAWKINS A, 1947, 454 MAIN AGR EXPT ST, P243
- [5] HILL WL, 1964, SUPERPHOSPHATE ITS H, P97
- [7] IBACH DB, 1964, 348 US DEP AGR STAT, P39
- [8] MAZOR E, 1963, ISR J EARTH SCI, V12, P41
- [10] PIERRE WH, 1953, SOIL FERTILIZER PHOS, P413