[1] Dumas studied at the École des beaux-arts de Québec.
In 1969, he moved to California to study at the Academy of Art University in San Francisco after being recommended by Jean Paul Lemieux.
[3] In 1970, he published À l'enseigne d'antan, a perspective on traditional Québécois insignias.
[4] He created three stamps for Canada Post to commemorate Germaine Guèvremont, Marie-Marguerite d'Youville, and the 25th Quebec Winter Carnival.
[6] He directed a specialized program in graphic communications at Université Laval from 1970 to 1973.