Real-time implementation and performance of a 16 kb/s low-delay CELP speech coder. - Juin-Hwey Chen; Melvin J. Melchner; Richard V. Cox; Duane O. Bowker (ICASSP, 1990)

Overview and performance of CCITT/ANSI embedded ADPCM algorithms. - Mostafa Hashem Sherif; Duane O. Bowker; Guido Bertocci; Bruce A. Orford; Gonzalo A. Mariano (IEEE Trans. Commun., 1993)