Downloading CQL

- CQL may be downloaded in zip format from here

- Harold van der Heijden's database of chess studies, Endgame Study Database 2015 can be purchased from his website Harold van der Heijden Database V 2015.

  But any PGN-file with studies can be used.

- A tool by Emil Vlasák that makes CQL easier to use, is available from Visual CQL.

- The given examples can be downloaded as a from here or copied from the example-pages.

- The introduction article by Gady Costeff can be downloaded from here: chess_query_language.pdf .

- Other sites with explanations and implementations are: Scidb and PGN.