Improved CELP coding using adaptive excitation codebooks. - U. Kipper; Herbert Reininger; Dietrich Wolf (ICASSP, 1991)

Low bit rate speech coding using CELP with adaptive excitation codebook. - U. Kipper; Herbert Reininger; Dietrich Wolf (EUROSPEECH, 1991)

Improving the speech quality of CELP-coders by optimizing the long-term delay determination. - Ulrich Balss; U. Kipper; Herbert Reininger; Dietrich Wolf (EUROSPEECH, 1993)