Oxford Text Archive The Archive contains electronic versions of more than 1500 literary works by many major authors in Greek, Latin, English and a dozen or more other languages. You can go directly to the short title catalogue of works.
From the Columbia University Libraries/Information Services Copyright Advisory Office
Text Encoding Initiative
In order for electronic texts to be effectively searched and analyzed, they require some degree of markup, coding identifying key structural (and possibly content and/or display) features. In order to promote the most efficient use and exchange of a growing body of electronic text materials, efforts are being made by the scholarly and publishing community to establish standards for markup, and the standard that is emerging as that of SGML (Standard Generalized Markup Language) and, most recently XML (Extensible Markup Language), a simplified and more easily implementable version of the latter. Since SGML and XML describe a method for markup rather than prescribing a specific set of markup tags, a parallel effort has been made by the Text Encoding Initiative (TEI) to propose sets of tags that researchers and publishers should use in marking up texts, to facilitate the use of those texts by other scholars as well.
Columbia Libraries' RefWorks subscription is expiring on June 30, but you can continue to to manage your citations in the same way with other tools. Information about making the transition is available here.