PCem uses a bit of code from some other projects to add functionality to the program.
The following are projects used and their authors and copyright notices/licenses

DOSBox
======
The DOSBox Team
---------------

Sjoerd v.d. Berg <harekiet>
Peter Veenstra <qbix79>
Ulf Wohlers <finsterr>
Tommy Frössman <fanskapet>
Dean Beeler <canadacow>
Sebastian Strohhäcker <c2woody>
Ralf Grillenberger <h-a-l-9000>

nick_without_<> @ users.sourceforge.net

Licensed under the GNU General Public License 2.0

reSID
=====
Authors of reSID.

Dag Lem: Designed and programmed complete emulation engine.
Antti S. Lankila: Support 6581 filter distortion, envelope & voice nonlinearities, output amp clipping effects.

Licensed under the GNU General Public License 2.0

MiniVHD
=======
# Credits
MiniVHD Copyright (c) 2019 Sherman Perry

MiniVHD was made possible with the help of the following projects

### libxml2
**Project Home:** http://www.xmlsoft.org/
**License:** MIT (see src/libxml2_encoding.c for details)

### cwalk
**Project Home:** https://likle.github.io/cwalk/
**Licence:** MIT (https://github.com/likle/cwalk/blob/master/LICENSE.md)

Licensed under the MIT License

Slirp
=====
Slirp was written by Danny Gasparovski.
Copyright (c), 1995,1996 All Rights Reserved.

Slirp is maintained by Kelly Price <tygris+slirp@erols.com>

Slirp is free software; "free" as in you don't have to pay for it, and you
are free to do whatever you want with it.  I do not accept any donations,
monetary or otherwise, for Slirp.  Instead, I would ask you to pass this
potential donation to your favorite charity.  In fact, I encourage
*everyone* who finds Slirp useful to make a small donation to their
favorite charity (for example, GreenPeace).  This is not a requirement, but
a suggestion from someone who highly values the service they provide.

The copyright terms and conditions:

---BEGIN---

 Copyright (c) 1995,1996 Danny Gasparovski.  All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions
 are met:
 1. Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer.
 2. Redistributions in binary form must reproduce the above copyright
    notice, this list of conditions and the following disclaimer in the
    documentation and/or other materials provided with the distribution.

 THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
 AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
 DANNY GASPAROVSKI OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

---END---

This basically means you can do anything you want with the software, except
1) call it your own, and 2) claim warranty on it.  There is no warranty for
this software.  None.  Nada.  If you lose a million dollars while using
Slirp, that's your loss not mine.  So, ***USE AT YOUR OWN RISK!***.

If these conditions cannot be met due to legal restrictions (E.g. where it
is against the law to give out Software without warranty), you must cease
using the software and delete all copies you have.

Slirp uses code that is copyrighted by the following people/organizations:

Juha Pirkola.
Gregory M. Christy.
The Regents of the University of California.
Carnegie Mellon University.
The Australian National University.
RSA Data Security, Inc.

Please read the top of each source file for the details on the various
copyrights.