420A Amino Acid Analyser, England, 1989
1989
1989
circa 1965
1967
1967
circa 1969
1980
1971
circa 1980
circa 1972
circa 1980
1978
1962
1960
circa 1980
circa 1971
1980s
circa 1958
1970-1980
1975-1990
1968
1980
1955-1965
1979
1970-1996
1982
1985
circa 1980
1950
circa 1990
1961
1961
1970
1966
1970s
1944-1950
1969
circa 1974
1951
1970