United States. Bureau of the Budget and United States. Office of Management and Budget. "National Aeronautics and Space Administration," in United States. Bureau of the Budget and United States. Office of Management and Budget. "Fiscal Year 1970," Budget of the United States Government (January 15, 1969) : 404-405. https://fraser.stlouisfed.org/title/54/item/19024/toc/237678 , accessed on March 28, 2024.