Bibilographies and lists of linguistic articles
Linguistic Bibliography Online – 480,000 bibliographical descriptions of linguistic publications (general and language-specific theoretical linguistics). It covers all languages of the world, including Esperanto and interlinguistics, with specific attention to the inclusion of publications on endangered and lesser-studied languages.
MLA International Bibliography (Modern Language Association) is a searchable online database of more than 2.7 million records. It covers all aspects of modern languages and literature, including Esperanto, interlinguistics etc., which are added by Natalia Dankova on behalf of ESF (previously Detlev Blanke and Humphrey Tonkin).
Interlinguistics and Esperanto studies. Paths to the scholarly literature. Compiled by Detlev Blanke. “A significant number of publications on interlinguistics and Esperanto studies would be improved if their authors had a more thorough knowledge of the significant scholarly literature.” (p.2). Also in German and in Esperanto. Published 2004. An excellent and detailed overview of the field. Essential reading.
Doctoral theses and Masters’ dissertations
ESF hosts a list of Italian theses and dissertations relating to Esperanto, compiled by Alessandra Madella, (PDF download in Esperanto). The dissertations are kept as files at the digital library of the Italian Federation, and as paper copies at the National Library of Esperanto in Massa.