Henri Dulac was born in Fayence (France) in 1870. He graduated from Ecole Polytechnique (Paris, class of 1892) and obtained a Doctorate in Mathematics. He started to teach a class of mathematic analysis at University, in Grenoble (France), Algiers (today Algeria) and Poitiers (France). Holder of a pulpit in pure mathematics in the Sciences University of Lyon (France) in 1911, his teaching was suspended during the first world war (1914 â€“ 1918) and he had to serve as officer in the French army. After the war, he became holder of a pulpit of differential and integral calculus and also taught in Ecole Centrale Lyon. He became examiner at Ecole Polytechnique (Paris) and President of the admission jury. Awarded Officer of Legion d'honneur, the French order established by Napoleon and associate member of the French Academy of Sciences, he published part of Euler's works and contributed to the research through many publications in France and abroad.
Father of 3 children, Anie (1901 â€“ 1935), bachelor in mathematics, Jean (1903 â€“ 2005), graduate of Ecole Polytechnique, 1921 and Robert (1904  1996), graduate of polytechnique, 1922; he died in Fayence, France, in 1955.
Among his publications :
â€˘ Recherches sur les points singuliers des Ă©quations diffĂ©rentielles (Journal of Ecole Polytechnique, 1904). â€˘ IntĂ©grales dâ€™une Ă©quation diffĂ©rentielle (Annales University of Grenoble, 1905). â€˘ Sur les Points dicritiques (Journal of mathĂ©matics, 1906). â€˘ Sur les sĂ©ries de MacLaurin Ă plusieurs variables (Acta Mathematica, 1906). â€˘ DĂ©termination et intĂ©gration dâ€™une classe dâ€™Ă©quations diffĂ©rentielles (Bulletin of mathematical sciences). â€˘ IntĂ©grales passant par un point singulier (Rendeconti del Circolo, 1911). â€˘ Sur les points singuliers (Annales, Toulouse, 1912). â€˘ Solutions dâ€™un systĂ¨me dâ€™Ă©quations diffĂ©rentielles (Bulletin of the mathematical society, 1913). â€˘ Sur les cycles limites (Bulletin of the mathematical society, 1923). â€˘ Points singuliers des Ă©quations diffĂ©rentielles (MĂ©morial des sciences mathĂ©matiques, 1932). â€˘ Courbes dĂ©finies par une Ă©quation diffĂ©rentielle du premier ordre (MĂ©morial des sciences mathĂ©matiques, 1934).
His researches are still mentioned or challenged by international university PHD students and professors, even a hundred years after being published. As an example :
â€˘ The Center Variety of Polynomial Differential Systems â€“ Abdu Salam Jarrah, FacultĂ© des sciences mathĂ©matiques, UniversitĂ© du Nouveau Mexique, USA (2001). â€˘ Complete Polynomial Vector Fields on C2 â€“ Julio Rebelo, Institute for Mathematical Sciences, SUNY, New York, USA (oct. 2002). â€˘ Dimension Increase and Splitting for PoincarĂ©Dulac Normal forms  Giuseppe Gaeta, FacultĂ© de MathĂ©matique de lâ€™UniversitĂ© de Milan and Sebastian Walcher, chaire de MathĂ©matique, Aix La Chapelle, Journal of Non linear Mathematical Physices (2005).
Sources : Technica, nÂ° 190, nov. 1955, Ecole Centrale Lyon, French Academy of Sciences, updated by Louis Boisgibault, his great grand son.
