A Digital Codec Simulation Facility. - William R. Daumer (IEEE Trans. Commun., 1978)

Subjective quality of several 9.6-32 kb/s speech coders. - William R. Daumer; J. L. Sullivan (ICASSP, 1982)

Subjective Evaluation of Several Efficient Speech Coders. - William R. Daumer (IEEE Trans. Commun., 1982)

Two approaches for waveform coding of 9.6 kbit/s voiceband data signals through 32 kbit/s ADPCM. - Nevio Benvenuto; William R. Daumer (IEEE Trans. Commun., 1988)