Andrew Kuchling has created Quotation Exchange Language (QEL), for the encoding of quotation collections.

Kuchling has created a DTD for QEL, and also a set of tools for processing QEL files. These tools include a Python library for QEL processing, and two command line scripts: qtformat and qtgrep, for formatting and searching QEL files. Kuchling warns that these tools are in early stage (v0.0.1!) development.

A collection of quotations encoded in QEL is available from Kuchling's web site. Kuchling writes:

[I] would like to convert some other quotation collections into QEL format (preferably public domain collections, or ones where the author grants me permission). Suggestions for useful QEL content would be appreciated.