"États-Unis. Vocational division." . . . . . . . . . . "Conserving farm lands planning for soil-erosion control, water conservation and efficient land use, by Tom Dale,... and W. A. Ross,... [Foreword by J. C. Wright.]" . . . . . . . . . . . . . . . . . . "Conserving farm lands planning for soil-erosion control, water conservation and efficient land use"@en . . "Conserving farm lands : planning for soil-erosion control, water conservation and efficient land use" . . . . . "Organized teaching material conserving farm lands" . "Erozja." . .