:~$ apt-cache policy calibre
calibre:
  Installato: 2.20.0+dfsg-1
  Candidato:  2.20.0+dfsg-1
  Tabella versione:
 *** 2.20.0+dfsg-1 0
        500 http://it.archive.ubuntu.com/ubuntu/ vivid/universe amd64 Packages
        100 /var/lib/dpkg/status