http://hsqldb.sourceforge.net/
http://www.sssg.org/wiki/index.jsp?pid=HSQLDB
http://www-6.ibm.com/jp/developerworks/opensource/040220/j_os-echsql.html
http://www.okapiproject.com/java/java_tips/tips_hsqldb.htm
http://www.wakhok.ac.jp/~tomoharu/db2004/hsqldb/