after gaining a d.phil. from friedrich-wilhelms universität in berlin in 1932 he earned a ph.d. at the university of cambridge in 1935 and a doctor of science at the university of manchester in 1954. his doctoral students included gilbert baumslag, lászló kovács, michael newman, and james wiegold. after war service with the british army, he became a lecturer at university college, hull, before moving in 1948 to the university of manchester, where he spent the next 14 years. in 1954 he received a dsc from the university of cambridge.