This primary source comes from the Records of the Environmental Protection Agency.
National Archives Identifier:
549655Full Citation: Vienna's Trolley System Is Efficient And Well-Scheduled. Some Of The Lines Are Underground; 7/1973; Records of the Environmental Protection Agency, Record Group 412. [Online Version, https://docsteach.org/documents/document/viennas-trolley-system-is-efficient-and-wellscheduled-some-of-the-lines-are-underground, September 9, 2024]