@InProceedings{michaelis97icassp, author = {M. Michaelis and R. Herpers and L. Witta and G. Sommer}, title = {Hierarchical filtering scheme for the detection of facial keypoints}, year = {1997}, publisher = {IEEE Computer Society Press}, booktitle = {Proc. of the Int. Conf. on Acoustics, Speech and Signal Processing, ICASSPŽ97, M{"u}nchen,}, pages = {2541--2544} }