This 139-page PDF file is the study commissioned by section 9of the Urban Mass Transportation Assistance Act of 1970. That law required the Department of Transportation to study the feasibility of the federal government providing direct operating subsidies to local mass transit providers.
The completed study was sent to Congress on November 22, 1971.
This copy was located in the “Mass Transit Operating Subsidies [2 of 2]” folder, in Box 21; White House Central Files: Staff Member and Office Files: Michael Raoul-Duval; at the Richard Nixon Presidential Library.