Potential means of cost reduction in grade crossing automatic gate systems. Volume II: improved gate arm concepts for railroad/highway grade crossings. Final report.

Transportation Systems Center, Cambridge, Mass.

The inventions, researches and writing of Nikola Tesla : with special reference to his work in polyphase currents and high potential lighting /

"Originally published in 1894 by the Electrical Engineer, New York."

U.S. Geological Survey-Missouri Geological Survey symposium : mineral-resource potential of the mid-continent : program and abstracts : St. Louis, Missouri, April 11-12, 1989 /

Mode of access: Internet.