Claus Boyens Ramayya Krishnan Rema Padman On Privacy-Preserving Access to Distributed Heterogeneous Healthcare Information. 2004 HICSS http://csdl.computer.org/comp/proceedings/hicss/2004/2056/06/205660135babs.htm db/conf/hicss/hicss2004-6.html#BoyensKP04