University of Michigan: Middle English Dictionary
Allen and Greenough's Latin Grammar: An On-line Reference Grammar
Internet Archive: A Dictionary of the Norman or Old French language (e-book)
Internet Archive: Grammar of the Gothic Language (e-book)
University of Texas: Old Irish Online
University of Texas: Old Church Slavonic Online
University of Texas: Old French Online
University of Pennsylvania: An Old High German Primer, Second Edition
University of Virginia: Old English
University of Texas: Old Norse Online
University of Texas: Gothic Online