Two more ideas you could try...

1) Using a hash to store the data:

#!/usr/bin/perl
use strict;

  my $data=();

  open(IN,"xxxx.in");
  while(<IN>){
     /<(\w+)>(.*)<\/\1>/;
     $data{$1} = $2;
  }
  close(IN);

print "Volume: $data{volume}\n";
print "Issue: $data{issue}\n";
print "Year: $data{year}\n";
[download]

2) Similar to the above but skipping the hash to make things a bit tighter:

#!/usr/bin/perl
use strict;

  open(IN,"xxxx.in");
  while(<IN>) {
    /<(\w+)>(.*)<\/\1>/;
    print ucfirst($1).": $2\n";
  }
  close(IN);
[download]

The \1 is a back reference to whatever got matched in the first set of <>'s. You don't strictly need it as /<(\w+)>(.*)</ works just as well but it gives it all a nice sense of symmetry :D

The ucfirst is just there to make the tags neat but naturally you could just write the tags like that in the first place if you desired.

Both solutions work dynamically so you can change your tag names or add / remove tags without needing to modify your code. They should just as easily handle:

<volume>4</volume>
<issue>12</issue>
<year>2003</year>
<pages>200</pages>
<author>A N Other</author>
[download]

... which will produce:

Volume: 4
Issue: 12
Year: 2003
Pages: 200
Author: A N Other
[download]