A Belgian mathematician Théophile H.J. Lepage (1901–1991) was a student of Théophile de Donder at the Université libre de Bruxelles where he defended his dissertation "Sur les propriétés invariantives des covariants symétriques gauches" in 1929. He was professor of mathematics at the University of Liège (1928–1930), at Université libre de Bruxelles (1931–1971), and a member of the Royal Academy of Science, Letters and Fine Arts of Belgium.

See also the following web sources: Wikipedia, Mathematics Genealogy Project