This work was done jointly with his doctoral student K A Fowler, and in 1955 they published a major paper which was to set mathematicians on the road to the classification.
Ang trabaho ay tapos na sama-sama sa kanyang mga mag-aaral ng doktor KA Fowler, at sa 1955 sila na nai-publish ng isang malaking papel na kung saan ay na-set mathematicians sa ang daan sa pag-uuri.