Elizabeth S. Helfman

Identifiers

  • Open LibraryOL835410A

Top Subjects

  • Hydrology (1)
  • Land use (1)
  • Water resources development -- United States. (1)
  • Watersheds -- United States. (1)
  • Rivers -- United States. (1)
  • Hydraulic machinery -- Juvenile literature (1)
  • Irrigation -- Juvenile literature (1)

Books by Elizabeth S. Helfman

Total count: 18