Retroflex consonants and dorsal /r/: mutually excluding innovations? On the diffusion of dorsal /r/ in Scandinavian

This contribution is a classical dialectological study which provides us with an overview of the /r/ variants found in the different Nordic (North Germanic) languages, i.e. the Scandinavian languages (Danish, Norwegian and Swedish) and the Insular Nordic languages (Faroese and Icelandic). Outside Denmark /r/ is almost everywhere a clearly consonantal phoneme, normally an apical (or coronal) vibrant or tap. In Danish there is widespread vocalisation of /r/ in rhyme position, like in most varieties of Continental Germanic (German and Dutch) and British English. Next, he gives an overview of the distribution of retroflex consonants and the dorsal /r/ in the area where Scandinavian languages are spoken (i.e. Denmark, Norway, Sweden and parts of Finland) both historically and presently. He explains their distribution by the hypothesis that dorsal /r/ and retroflex consonants do not occur within one and the same dialect, a co-occurrence constraint that needs to be modified because of the special role of r-vocalisation