In 1979 he received his doctoral degree with a dissertation about a text by the author Breyten Breytenbach and some of whose books van Dis has translated into Dutch .
Breyten Breytenbach was to influence his later writing .
In 1979 he received his doctoral degree with a dissertation about a text by the author Breyten Breytenbach , who was to influence his later writing , and some of whose books van Dis has translated into Dutch .