Kenneth L. Calvert Jim Griffioen Najati Imam Jiangbo Li Challenges in Implementing an ESP Service. 3-19 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2982&spage=3 2003 conf/iwan/2003 IWAN db/conf/iwan/iwan2003.html#CalvertGIL03