http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
a survey of main line and rapid transit systems in many countries
Conference on Performance of Electrified Railways, (1968 : London)
organized by the Power Division of the Institution of Electrical Engineers.
v. 1. Contributions. --v. 2. Record of discussions.