Kun Yue Zhengchuan Xu Zhimao Guo Aoying Zhou Constraint Preserving XML Updating. 47-58 2003 conf/apweb/2003 APWeb http://link.springer.de/link/service/series/0558/bibs/2642/26420047.htm db/conf/apweb/apweb2003.html#YueXGZ03