Bibliographies ; Reprints ; Meta analysis; Literaturstudie; Literature review; Scientific review ; History of linguistics (19th century) ; State of the art ; Phylogenese; Biolinguistics ; Natural language ; Sign ; Comparative linguistics; Komparatistik; Indogermanistik; Indoeuropäische Sprachwissenschaft; Indoeuropean linguistics; Proto-Indo-European; Historical comparative linguistics ; Indogermanisch; Indo-European languages