1. Career Development of Scientists, Harvard Graduate School of Education, Cambridge, Massachusetts, 1963. U. S. Office of Education Cooperative Research Project Number 436. This report has been distributed to libraries of the Documents Expediting Project, Library of Congress.
2. This overlapping design was adapted from an approach first proposed by in Research Conference on the Identification of Creative Scientific Talent, editor, University of Utah Press, Salt, Lake City, 1956.
3. Approaching Ceilings in the Supply of Scientific Manpower
4. D. Wolfle pointed out the need for this type of research at a 1956 conference on scientific careers. See and , Scientific Careers and Vocational Development Theory, Teachers College, Columbia University, 1957, p. 101.