A Proposal to Add Hash Tables to the Standard Library http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2003/n1456.html The hash table proposal explains much of the design. The hash function object is discussed in Section D.
The C++ Standard Library Technical Report. http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/n1836.pdf Contains the hash function specification in section 6.3.2.
Library Extension Technical Report Issues List. http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/n1837.pdf The library implements the extension described in Issue 6.18, pages 63-67.
Methods for Identifying Versioned and Plagiarised Documents
Timothy C. Hoad, Justin Zobel http://www.cs.rmit.edu.au/~jz/fulltext/jasist-tch.pdf
Contains the hash function that
is based on.