In 1964 , he gained his Ph. D there .
That same year , Lewin was awarded a research scholarship to the Sorbonne in Paris , where he studied the collectivization of Soviet agriculture .
In 1964 , Lewin gained Lewin 's Ph. D there .
That same year , Lewin was awarded a research scholarship to the Sorbonne in Paris , where he studied the collectivization of Soviet agriculture .