Case study (language acquisition) ; Spracherwerb (lex.) ; Language acquisition (lex.) ; Vocabulary (language acquisition) ; Dual language acquisition; Bimodal language acquisition; Spracherwerb (biling.) ; Language acquisition (biling.) ; Bilingual language acquisition ; Bilingual mental lexicon; Lexicon (biling.) ; Österreichisch; Austria (German language in) ; Österreich (dt. Sprache in) ; Bairisch in Österreich; Bavarian in Austria; German in Austria ; Italian