conf/sigmod/83 David Maier Jeffrey D. Ullman Fragments of Relations. 15-22 1983 SIGMOD Conference db/conf/sigmod/sigmod83.html#MaierU83 SIGMOD83/P015.PDF http://doi.acm.org/10.1145/582192.582200 db/conf/sigmod/MaierU83.html books/aw/AhoHU74 ... ... conf/sigmod/EpsteinSW78 ... journals/tods/RothnieBFGHLRSW80 conf/berkeley/RothnieG77