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Introduction to OmegaT (2.5.0). By Arno Peters and Mariëtte van Drunen (in Dutch).
Review of OmegaT 2.3.0. By Václav Hejda (in Czech).
Review of OmegaT 1.6 RC5. By Yutaka Kachi (in Japanese).
Description of OmegaT (2008). By Asier Sarasua Garmendia (in Basque).
Review of OmegaT 1.6.1_1. By Takashi Miyamoto (in Japanese).
Review of OmegaT, 11 April 2008. By Corinne McKay (in English).
Review of OmegaT, 2010. By Leo Viëtor (in Dutch).
Review of OmegaT, 2009. In PCW.GR (in Greek).
Brief introduction to OmegaT, 2009 (in Vietnamese).
Degree thesis by Sébastien Guillardeau, 2010 (in German). Contains a comprehensive description of OmegaT.
Mini-review of OmegaT, 2012.
OmegaT on Wikipedia (at the time of writing, in fifteen languages).