- 1950Research Associate
- 1964[position unknown]
- 1948Research Associate
- 1949Research Associate
- 1959[position unknown]
- 1960[position unknown]
- 1961[position unknown]
- 1962[position unknown]
- 1963[position unknown]
- 1964[position unknown]
- 1965[position unknown]
- 1966[position unknown]
- 1967[position unknown]
- 1968[position unknown]
- 1969[position unknown]
- 1970[position unknown]
- 1971[position unknown]
- 1972[position unknown]
- 1973[position unknown]
- 1974[position unknown]
- 1975[position unknown]
- 1976[position unknown]
- 1977[position unknown]
- 1978[position unknown]
- 1979[position unknown]
- 1980[position unknown]
- 1981[position unknown]
- 1982[position unknown]
- 1984[position unknown]
- 1985[position unknown]
- 1986[position unknown]
- 1987[position unknown]
- 1950Research Associate