Passive Transpiration Cooled Re-Entry Head Shield Development for Radioisotopic Heat Sources, No. 68SD286, 1968-08-15, Box: 1 , Folder: 36. Jonathan Black papers, 16-18-4522. Division of Rare and Manuscript Collections. https://aspace3-test.library.cornell.edu/repositories/2/archival_objects/972329 Accessed July 07, 2026.