Low bit-rate spectral coding in CELP, a new LSP-method. - Roar Hagen; Per Hedelin (ICASSP, 1990)

Robust vector quantization in spectral coding. - Roar Hagen; Per Hedelin (ICASSP (2), 1993)

Spectral quantization of cepstral coefficients. - Roar Hagen (ICASSP (1), 1994)

Variable rate spectral quantization for phonetically classified CELP coding. - Roar Hagen; Erdal Paksoy; Allen Gersho (ICASSP, 1995)

On Robust LPC-spectrum Coding and Vector Quantization. - Roar Hagen (1995)

A low-complexity waveform interpolation coder. - W. Bastiaan Kleijn; Yair Shoham; Deep Sen; Roar Hagen (ICASSP, 1996)

On memoryless quantization in speech coding. - W. Bastiaan Kleijn; Roar Hagen (IEEE Signal Process. Lett., 1996)

Robust LPC spectrum quantization-vector quantization by a linear mapping of a block code. - Roar Hagen (IEEE Trans. Speech Audio Process., 1996)

Using a perception-based frequency scale in waveform interpolation. - Jes Thyssen; W. Bastiaan Kleijn; Roar Hagen (ICASSP, 1997)

Removal of sparse-excitation artifacts in CELP. - Roar Hagen; Erik Ekudden; Björn Johansson; W. Bastiaan Kleijn (ICASSP, 1998)

ITU-t g.729 extension at 6.4 kbps. - Erik Ekudden; Roar Hagen; Björn Johansson; Shinji Hayashi; Akitoshi Kataoka; Sachiko Kurihara (ICSLP, 1998)

An 8 kbit/s ACELP coder with improved background noise performance. - Roar Hagen; Erik Ekudden (ICASSP, 1999)

Voicing-specific LPC quantization for variable-rate speech coding. - Roar Hagen; Erdal Paksoy; Allen Gersho (IEEE Trans. Speech Audio Process., 1999)

Robust Vector Quantization by a Linear Mapping of a Block Code. - Roar Hagen; Per Hedelin (IEEE Trans. Inf. Theory, 1999)

Internet Low Bit Rate Codec (iLBC). - Søren Vang Andersen; Alan Duric; Henrik Astrom; Roar Hagen; W. Bastiaan Kleijn; Jan Linden (RFC, 2004)