title: List previous versions available for a package and install one of them by apt-get
body: <p>A <code>10.5-2</code> version of <code>postgresql</code> that is coming from the<br>
  <code>deb http://apt.postgresql.org/pub/repos/apt/ stretch-pgdg main</code><br>
  repository has a problem, and I would like to return to the <code>10.4</code> version I know to be working the way I want.</p>
  
  <p>an <code>apt-cache madison postgresql-10</code> returns me these informations atm :<br>
  <code>postgresql-10 | 10.5-2.pgdg90+1 | http://apt.postgresql.org/pub/repos/apt stretch-pgdg/main amd64 Packages
  postgresql-10 | 10.5-2.pgdg90+1 | http://apt.postgresql.org/pub/repos/apt stretch-pgdg/main Sources</code></p>
  
  <p>How can I find the previous packages version(s) existing for <code>10.4</code> ?<br>
  When I try to use a version number I found somewhere (on chocolatey website : I had no clue about how to search and was a bit lost), it didn't succeed :
  <code>sudo apt-get install postgresql-10=10.4.0.20180721
  E: Version '10.4.0.20180721' for 'postgresql-10' was not found</code></p>
  
  <p>Going to the <code>postgresql</code> repository, <a href="http://apt.postgresql.org/pub/repos/apt/dists/stretch-pgdg/" rel="nofollow noreferrer">http://apt.postgresql.org/pub/repos/apt/dists/stretch-pgdg/</a>, I didn't found a clue about how to get any previous version.</p>
  
  <p>More generally, what is the way, through command line and aptitude commands, to list what previous versions can be installed for a package ?<br>
  Is there, for example, a standard that set another location for previous versions, like an archive repository I should always find in the form <a href="http://../" rel="nofollow noreferrer">http://../</a><strong>archive</strong>/../, or something else ?</p>
  
  <p>Thanks !</p>