Reference:

Sami Virpioja and Mikko Kurimo. Compact n-gram models by incremental growing and clustering of histories. In Proceedings of 9th International Conference on Spoken Language Processing (Interspeech 2006 – ICSLP), pages 1037–1040, Pittsburgh, PA, USA, September 2006.

Suggested BibTeX entry:

@inproceedings{virpioja06is,
    address = {Pittsburgh, PA, USA},
    author = {Sami Virpioja and Mikko Kurimo},
    booktitle = {Proceedings of 9th International Conference on Spoken Language Processing (Interspeech 2006 -- ICSLP)},
    month = {September},
    pages = {1037--1040},
    title = {Compact n-gram models by incremental growing and clustering of histories},
    year = {2006},
}