Europe ; History of linguistics (20th century) ; Amtssprache; Official language; National language ; Ökologie und Sprache; Ecology and language; Umweltschutz; Pollution; Umweltbelastung; Ökolinguistik; Ecolinguistics; Klimawandel; Climate change; Language and ecology ; Sprachenpolitik; Language management; Language politics ; Language diffusion; Language shift; Sprachwechsel; Language spread ; Cercle linguistique de Prague; Prague Linguistic Circle; Prague school
