Josef Spillner Martin Beck Alexander Schill Thomas Michael Bohnert Stealth Databases: Ensuring User-Controlled Queries in Untrusted Cloud Environments. 261-270 2015 UCC https://doi.ieeecomputersociety.org/10.1109/UCC.2015.44 conf/ucc/2015 db/conf/ucc/ucc2015.html#SpillnerBSB15