History of linguistics (20th century) ; State of the art ; Sign language ; Vlaamse Gebarentaal; VGT; Flemish Sign Language ; Category (theory of grammar) ; Gesture communication ; Speech production, modality-specific; Speech perception, modality-specific; Sprachproduktion, modalitätsspezifische; Sprachperzeption, modalitätsspezifische; Gebärdensprache/Lautsprache; Sign language/vocal language; Modality-specificity
