Arthème Camille Matignon (French pronunciation: [kamij matiɲɔ̃]; 3 January 1867 – 18 March 1934) was a French chemist noted for his work in thermochemistry. He was a member of the Académie des Sciences, President of the French Chemical Society and an honorary Fellow of the British Chemical Society.
Paul-Émile Lecoq de Boisbaudran, also called François Lecoq de Boisbaudran (18 April 1838 – 28 May 1912), was a French chemist known for his discoveries of the chemical elements gallium, samarium and dysprosium. He developed methods for separation and purification of the rare earth elements and was one of the pioneers of the science of spectroscopy.