conf/vldb/93 Antonio Albano Roberto Bergamini Giorgio Ghelli Renzo Orsini An Object Data Model with Roles. 39-51 1993 VLDB db/conf/vldb/vldb93.html#AlbanoBGO93 db/conf/vldb/AlbanoBGO93.html VLDB93/P039.PDF journals/tods/AlbanoCO85 conf/vldb/AlbanoGO91 conf/dbpl/AlbanoGO91 conf/vldb/BachmanD77 journals/tois/FishmanBCCCDDHKLMNRS87 conf/oopsla/BlackHJL86 conf/sigmod/RichardsonS91 conf/oopsla/ShillingS89 ... conf/vldb/Su91