This is Mozilla, source can be retrieved from mozilla.org by either
FTP or HTTP

http://ftp.mozilla.org/pub/mozilla/releases/mozilla<version>/src/
ftp://ftp.mozilla.org/pub/mozilla/releases/mozilla<version>/src/

Upstream web site: http://www.mozilla.org/

Copyright from about:
==
Copyright (C) 1998-2004 by Contributors to the Mozilla codebase under the Mozilla Public License and Netscape Public License.

Portions of this software are copyright (C) 1994 The Regents of the University of California. All Rights Reserved.

Portions of this software are copyright (C) Japan Network Information Center. All Rights Reserved.

This software may contain portions that are copyright (C) 1998-2002 SupportSoft, Inc. All Rights Reserved.

U.S. GOVERNMENT END USERS. The Software is a "commercial item," as that term is defined in 48 C.F.R. 2.101 (Oct. 1995), consisting of "commercial computer software" and "commercial computer software documentation," as such terms are used in 48 C.F.R. 12.212 (Sept. 1995). Consistent with 48 C.F.R. 12.212 and 48 C.F.R. 227.7202-1 through 227.7202-4 (June 1995), all U.S. Government End Users acquire the Software with only those rights set forth herein. 
==

Name of contributers can be browse with "about:credits" as URL in mozilla browser.

Some files in this source package are under the Netscape Public License
Others, under the Mozilla Public license, and just to confuse you even 
more, some are dual licensed MPL/GPL.

The full text of the NPL and MPL are in the same directory as this file
with the filenames NPL-1.1.txt and MPL-1.1.txt, and may be compressed.

The full text of the GPL is in /usr/share/common-licenses/GPL
