Günther Pernul Alexander W. Röhm Gaby Herrmann Trust for Electronic Commerce Transactions. 1-13 ADBIS/1999/16910001.pdf 1999 ADBIS db/conf/adbis/adbis99.html#PernulRH99 conf/adbis/99 db/conf/adbis/PernulRH99.html http://link.springer.de/link/service/series/0558/bibs/1691/16910001.htm ... ... ... ... ... ... ... ... ... ... journals/cacm/CurtisKO92 ...