No access restrictions. Many of SIA's holdings are located off-site, and advance notice is recommended to consult a collection. Please email the SIA Reference Team at osiaref@si.edu
Duckworth, W. Donald and Eichlin, Thomas D. 1973. "New Species of Clearwing Moths (Lepidoptera: Sesiidae) from North America." Proceedings of the Entomological Society of Washington, 75 150–159.
Ayensu, Edward S. 1973. "Phytogeography and Evolution of the Velloziaceae." In Comparative Evolution of Tropical Forest Ecosystems in Africa and South America. Meggers, Betty J., Ayensu, Edward S., and Duckworth, W. Donald, editors. 105–119. Washington: Smithsonian Press.
Fosberg, F. Raymond. 1973. "Temperate Zone Influence on Tropical Forest Land Use: A Plea for Sanity." In Tropical Forest Ecosystems in Africa and South America. Meggers, Betty J., Ayensu, Edward S., and Duckworth, W. Donald, editors. 345–350. Washington: Smithsonian Press.
Meggers, Betty J. and Evans, Clifford. 1973. "Some Problems of Cultural Adaptation in Amazonia with Emphasis on the Pre-European Period." In Tropical Forest Ecosystems in Africa and South America: A Comparative Review. Meggers, Betty J., Ayensu, Edward S., and Duckworth, W. Donald, editors. 311–320. Smithsonian Institution Press.