Théorie Élémentaire de la Botanique is a book written by Swiss botanist Augustin Pyramus de Candolle, which was first published in 1813 and later re-issued in 1819 with a new edition. This book contributed to the field of botany by introducing the use of the term taxonomy and a new classification system for grouping plants together. This book placed emphasis on the study of evolutionary relationships in grouping plants together, rather than on shared morphological characteristics. Source: Wikipedia (en)