H. Hsu Nick Roussopoulos Database Conceptual Modelling. 259-276 1979 ER db/conf/er/er79.html#HsuR79 conf/er/79 er79/ER79-P259.pdf conf/ds/Abrial74 ... journals/tods/Bernstein76 conf/sigmod/Codd79 journals/tods/Fagin77 conf/ds/Falkenberg76 ... conf/ds/HallOT76 journals/cacm/HammerHKW77 ... ... ... ... ... conf/db-workshops/Palmer78 ... ... journals/cacm/SmithS77 journals/tods/SmithS77