This file contains citations for papers that contain the relational identities
upon which the transformation rules are based. Some rules contain a "Citations"
line which references one or more entries in this list of citations, in which
further information, and in some cases proofs, can be found.

[1] Galindo-Legaria, C.A. & Rosenthal, Arnon. (1997).
    Outerjoin Simplification and Reordering for Query Optimization.
    ACM Trans. Database Syst.. 22. 43-73. 10.1145/244810.244812.
    https://www.researchgate.net/publication/220225172_Outerjoin_Simplification_and_Reordering_for_Query_Optimization

[2] M. M. Joshi and C. A. Galindo-Legaria.
    Properties of the GroupBy/Aggregate relational operator.
    Technical report, Microsoft, 2001. MSR-TR-2001-13.

[3] Galindo-Legaria, C.A. & Joshi, Milind. (2001).
    Orthogonal Optimization of Subqueries and Aggregation.
    Sigmod Record. 30. 571-581. 10.1145/375663.375748. 
    http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.563.8492&rep=rep1&type=pdf

[4] Galindo-Legaria, C.A.. (2001).
    Parameterized queries and nesting equivalences.
    https://www.microsoft.com/en-us/research/wp-content/uploads/2016/02/tr-2000-31.pdf

[5] Elhemali, Mostafa & Galindo-Legaria, C.A. & Grabs, Torsten & M. Joshi, Milind. (2007).
    Execution strategies for SQL subqueries.
    993-1004. 10.1145/1247480.1247598.
    https://www.researchgate.net/profile/Mostafa_Elhemali/publication/221213885_Execution_strategies_for_SQL_subqueries/links/584f631308aecb6bd8d02aa4/Execution-strategies-for-SQL-subqueries.pdf

[6] Simmen, David & Shekita, Eugene & Malkemus, Timothy. (1996).
    Fundamental Techniques for Order Optimization.
    Sigmod Record. Volume 25 Issue 2, June 1996. Pages 57-67.
    https://cs.uwaterloo.ca/~gweddell/cs798/p57-simmen.pdf
