Occidental Language - A brief description of Occidental (Interlingue). - http://en.wikipedia.org/wiki/Occidental_language
Interlingue-Union - Official site for the organisation. It gives information about the Union and the Interlingue language, by Edgar von Wahl. - http://www.interlingue.org/
H. Jacob on Occidental - Its history, grammar and vocabulary. - http://interlingue.narod.ru/eng.html
Bibliotheca Occidental - History, progress, regulations, theory and reality of Occidental. - http://amor.rz.hu-berlin.de/~h0444wow/index.html