@InProceedings{sommer93b, author = "M. Michaelis and G. Sommer", title = "Characterization of key-points in images", address = "Innsbruck", editor = "J.-L. Flanagan", booktitle = {Proc. Conf. Substance Identification Technologies, SPIE Proceedings Series Vol. 2093}, pages = "450-461", year = 1993 }