Multiclass linear dimension reduction by weighted pairwise Fisher criteria
M. Loog, R.P.W. Duin, R. Haeb-Umbach, IEEE Transactions on Pattern Analysis and Machine Intelligence 23 (2001) 762–766.

LDA derived cepstral trajectory filters in adverse environmental conditions
M. Lieb, R. Haeb-Umbach, in: IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP 2000), 2000, pp. - vol.2.