An html version of mirrormate.cql. Created by Gady Costeff and Lewis Stiller.

; Find all positions with mirror mate in the main line. 
; A mirror mate is a Mating position in which all (eight) neighboring fields of the mated king are unoccupied. (match :pgn heijden.pgn :output mirrormate.pgn (position :attackcount k . 8 :mate ) )

After executing this with "> cql MirrorMate.cql" there are 59 studies found in the Harold van der Heijden Database 2015.
NB. When you see {MATCH} in the text, it means that cql has found the position asked for.

Below only 5 studies are presented: