conf/vldb/80 Nicolas Spyratos Translation Structures of Relational Views. 411-416 VLDB80/P411.PDF 1980 VLDB db/conf/vldb/vldb80.html#Spyratos80 conf/ifip/Armstrong74 ... journals/tods/BancilhonS81 ... conf/vldb/DayalB78 ... books/cs/Ullman80