Leonid Libkin Expressive Power of SQL. 1-21 2001 conf/icdt/2001 ICDT db/conf/icdt/icdt2001.html#Libkin01 http://dx.doi.org/10.1007/3-540-44503-X_1 http://link.springer.de/link/service/series/0558/bibs/1973/19730001.htm books/aw/AbiteboulHV95 conf/popl/AhoU79 journals/jcss/BarringtonIS90 journals/tcs/BunemanNTW95 books/mk/Celko99 journals/tcs/ConsensM93 books/aw/DateD97 journals/tcs/DongLW00 journals/tocl/GroheS00 journals/jcss/Etessami97 journals/iandc/FaginSV95 ... ... journals/iandc/GradelG98 ... journals/iandc/Hella96 ... conf/lics/HellaLNW99 ... journals/jacm/Klug82 conf/lics/Libkin97 journals/tocl/Libkin00 journals/jcss/LibkinW97 conf/dbpl/LibkinW97 books/mk/ONeil94 journals/jcss/ParberryS88 journals/jcss/RazborovR97 journals/mscs/Wadler92