N. Bernsen, и L. Dybkjær. Proceedings of the International CLASS Workshop on Information Presentation and Natural Multimodal Dialogue, Verona, Italy, стр. 75-79. (2001)
P. Bihler, M. Fotsing, G. Kniesel, и C. Joffroy. iiWAS '08: Proceedings of the 10th International Conference on Information Integration and Web-based Applications & Services, Linz, Austria, стр. 677-680. (2008)