Renewable Energy R&D Funding History: A Comparison with Funding for Nuclear Energy, Fossil Energy, Energy Efficiency, and Electric Systems R&D, report, June 18, 2018; (https://digital.library.unt.edu/ark:/67531/metadc1213117/m1/1/: accessed April 20, 2024), University of North Texas Libraries, UNT Digital Library, digital.library.unt.edu; .