Kalman filtering techniques in speech coding. - Sam Crisafulli; James D. Mills; Robert R. Bitmead (ICASSP, 1992)

Adaptive quantization: solution via nonadaptive linear control. - Sam Crisafulli; Robert R. Bitmead (IEEE Trans. Commun., 1993)

Variable bit rate ADPCM via arithmetic coding. - Craig R. Watkins; Sam Crisafulli; Robert R. Bitmead; Robert Orsi (ICASSP (1), 1994)

A coupled approach to ADPCM adaptation. - Sam Crisafulli; Gonzalo J. Rey; C. Richard Johnson Jr.; Rodney A. Kennedy (IEEE Trans. Speech Audio Process., 1994)

Destabilization effects of adaptive quantization in ADPCM. - Craig R. Watkins; Robert R. Bitmead; Sam Crisafulli (IEEE Trans. Speech Audio Process., 1995)

Nonlinear Obseryer Design for Adpcm Signal Coding Systems. - Sam Crisafulli; Robert R. Bitmead (ISSPA, 1996)