PNG images by Eric De Mund, licensed under creative commons attribution 4.0 international license.
SVG images from Colin M.L. Burnett, licensed under GFDL, CC-BY-SA-3.0 or GPL, via Wikimedia Commons.
The figurine fonts are derived from the Liberation Sans font released under GNU General Public License, with the addition of chess pieces from freeware fonts: the alpha2 font (Peter Strickland), the good companion font (David L. Brown), the merida font (Armando H. Marroquin), the pirate font (Klaus Wolf) and the chess usual font (Armando H. Marroquin). The original chess fonts and more details are available at the en passant site. The chess informant symbols font is used with permission from the Chess Informant publishing company. The chess ole figurin font is from the ChessOLE project (David Frank) and it is available at the en passant site.
Some of the PGN files for the examples are coming from The Week in Chess (file twic944.pgn), from the scid project (file tactics.pgn, with minor modifications) and from the Chess Informant publishing company (file chess-informant-sample.pgn).
The above items remains subject to their original licenses (if any).
Remaining pgn4web code is Copyright (C) 2009-2018 Paolo Casaschi.
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
See license-gpl-2.0.txt license file.
You are free to use pgn4web in your website or blog; you are not required to acknowledge the pgn4we project, but if you want to do so the following line might be used (please note pgn4web is always spelled with lowercase letters):
chess games viewer from <a href="http://pgn4web.casaschi.net">the pgn4web project</a>
You are also encouraged to notify firstname.lastname@example.org that you are using pgn4web.