conf/sigmod/90 Jeffrey D. Ullman Mihalis Yannakakis The Input/Output Complexity of Transitive Closure. 44-53 1990 conf/sigmod/90 SIGMOD Conference db/conf/sigmod/sigmod90.html#UllmanY90 http://doi.acm.org/10.1145/93597.93620 SIGMOD90/P044.PDF conf/vldb/AgrawalJ87 books/aw/AhoHU74 ... conf/stoc/CoppersmithW87 conf/stoc/HongK81 journals/cacm/HopcroftT73 conf/vldb/IoannidisR88 ... ... books/cs/Ullman88 books/cs/Ullman89 journals/cacm/Warren75 journals/jacm/Warshall62