the content of languages.txt is generated from the file
iso_639.xml which contains this copyright:

<?xml version="1.0" encoding="UTF-8" ?>
<!-- iso-639.tab                                                        -->
<!--                                                                    -->
<!-- Copyright (C) 2004 Alastair McKinstry   <mckinstry@computer.org>   -->
<!-- Released under the GNU License; see file COPYING for details       -->
<!--                                                                    -->
<!-- Last update: 2004-10-27                                            -->
<!--                                                                    -->
<!-- This file gives a list of all languages in the ISO-639             -->
<!-- standard, and is used to provide translations (via gettext)        -->
<!--                                                                    -->
<!-- Status: ISO 639-2:1998 + additions and changes until 2004-03-05    -->
<!-- Source: http://lcweb.loc.gov/standards/iso639-2/englangn.html      -->