Copyright for plum source package in Oracular

Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
Upstream-Name: plum
Upstream-Contact: Yoshinori Hasegawa 
Source: ftp://ftp.madoka.org/pub/plum/
Comment:
 Note that, there is no license description in the source code.
 The upstream maintainer mailed me (GOTO Masanori ) 
 as follows
 .
 Copyrightについては私がはっきりと意思表示していないために
 各方面でいろいろと御迷惑をおかけしているようで
 大変申し訳なく思っているのですが、これ以降、plumのCopyright
 はGPL2に従うようにして下さい。
 .
 (He declared that the license of the plum package follows GPL2.)

Files: *
Copyright: 1997-1999 Yoshinori Hasegawa 
License: GPL-2

Files: debian/*
Copyright: 1999-2006 GOTO Masanori 
           2016-2017 Hideki Yamane 
License: GPL-2

License: GPL-2
 This program is free software; you may redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation; version 2.
 .
 This 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.
 .
 A copy of the GNU General Public License version 2 is available as
 /usr/share/common-licenses/GPL-2 in the Debian GNU/Linux distribution
 or at http://www.gnu.org/licenses/old-licenses/gpl-2.0.html.