University of Maryland Libraries Hornbake Library 4130 Campus Drive
Navigate the Collection
6.1.60, Popenoe, C. H. -- Untapped Energy from the Sun, undated, Box: 1, Folder: 60.0. Tau Beta Pi records, 0046-UA. Special Collections and University Archives. https://archives.lib.umd.edu//repositories/2/archival_objects/201385 Accessed October 25, 2021.