IBM DB2 9.1 for Linux, Unix and Windows
documentation
DB2 Universal Database Version 9.1 is out of support as of April 30, 2012. More details are available here:
http://www-01.ibm.com/support/docview.wss?uid=swg21575777
DB2 Version 9.1 for Linux, UNIX and Windows manuals in PDF format can be found here:
https://www.ibm.com/support/pages/node/319045