Morphologische Untersuchungen auf dem Gebiete der indogermanischen Sprachen

Hermann Osthoff (1847-1909) and Karl Brugmann (1849-1919) were prominent members of the Neogrammarian school of linguistics. This six-volume work, published between 1878 and 1910, develops the theory that European languages, together with certain languages of central and southern Asia, have a common origin in a prehistoric Indo-European language.