conf/vldb/77 D. L. Childs Extended Set Theory. 28-46 VLDB77/P028.PDF 1977 VLDB db/conf/vldb/vldb77.html#Childs77 db/conf/vldb/Childs77.html ... conf/pacific/Beitz75 ... ... journals/cacm/CanadayHIRW74 ... ... ... journals/cacm/Codd70 persons/Codd72 ... journals/csur/Dodd69 ... ... ... conf/sigmod/Fry70 journals/csur/FryS76 ... ... ... ... ... ... ... books/aw/Knuth69 ... ... ... ... ... ... ... ... ... ... ... conf/sigmod/Sibley74 ... ... ... ... journals/iandc/Zadeh65