Soil, the most valuable mineral resource, its origin, destruction and preservation,
Twenhofel, William H. 1875-1957.
Soil, the most valuable mineral resource, its origin, destruction and preservation, by W. H. Twenhofel. - [Portland, 1944] - 45, [2] p. illus., plates. 28 cm. - Oregon. State Dept. of Geology and Mineral Industries. Bulletin no. 26 .
Reproduced from type-written copy.
"References cited": p. [46]-[47]
gs 44000046
Erosion.
Soil conservation.
QE155 / .A3 no. 26
631.45
Soil, the most valuable mineral resource, its origin, destruction and preservation, by W. H. Twenhofel. - [Portland, 1944] - 45, [2] p. illus., plates. 28 cm. - Oregon. State Dept. of Geology and Mineral Industries. Bulletin no. 26 .
Reproduced from type-written copy.
"References cited": p. [46]-[47]
gs 44000046
Erosion.
Soil conservation.
QE155 / .A3 no. 26
631.45