Jan Ketelaar

Jan Arnold Albert Ketelaar (21 April 1908, Amsterdam - 23 November 2001, Lochem) was a Dutch chemist and author of the textbook ''Chemical Constitution: an Introduction to the Theory of the Chemical Bond'' (). Van Arkel–Ketelaar triangles are named after him.

Ketelaar's doctoral students included Sol Kimel and Robert de Levie. He was elected a member of the Royal Netherlands Academy of Arts and Sciences in 1958. Provided by Wikipedia