@book{61888, author = {Spencer, Herbert, and Cazelles, Émile Honoré,}, title = {Principes de sociologie / }, publisher = {Librairie Germer Bailliere et Cie,}, year = {1878-1879.}, address = {Paris :}, url = {http://www.archive.org/stream/cu31924014322675#page/n7/mode/2up} }