UCA

The Unicode collation algorithm (UCA) "provides a standard way to put names, words or strings of text in sequence according to the needs of a particular situation." (Wikipedia)

References

Davis, Mark, and Ken Whistler. 2006. "Unicode Technical Standard #10: Unicode Collation Algorithm," http://www.unicode.org/reports/tr10/

Wikipedia, "Unicode collation algorithm," http://en.wikipedia.org/wiki/Unicode_collation_algorithm