Free tools used for this website

I would like to thank everyone who composed the chess problems featured in my website,
as well as the programmers of the tools that i'm using:

Chess database and PGN viewer
with Stockfish chess engine:
PGN ChessBook

Copy chess diagrams from one program
or web page to another quickly and easily:
DiagTransfer

Ultra fast duplicate file finder/remover:
Yet Another Duplicate File Remover

Here you can find a vast chess problem database
which includes the solutions, some information about the composers,
the year they were first appeared and where they were published.
Yet Another Chess Problem Database

Problemist for Windows is a shareware program written by Matthieu Leschamelle for Windows and Windows Mobile. Problemist solves direct mates, helpmates, selfmates and reflexmates. It can rotate positions, print diagrams and much more.
(Registration costs 25euros)
https://problemiste.pagesperso-orange.fr/