Canonical Text Services
Canonical Text Services identify and retrieve passages of text cited by canonical reference.
Description
The Canonical (previously 'Classical') Text Services specification defines a network service for identifying texts and retrieving fragments of texts using notions of "work" and "citation" traditional in classical studies and other literary disciplines.
Applications
One classical project which uses Canonical Text Services is the Homer Multitext (cf. information on its blog).
The Perseus Project also relies on CTS architecture, see [1].
Bibliography
A CiteULike CTS bibliography by Alison Babeu.
Older code and documentation addresses
URL: http://chs75.harvard.edu/projects/diginc/techpub/cts
The project also has a Sourceforge site, with more recent information: http://cts3.sourceforge.net/
There is a mailing list, too: https://lists.sourceforge.net/lists/listinfo/cts3-general