liz has the problem nailed down exactly. The solution, of course, is simple:

if ( $str =~ /^Title: (.*)\s+Author: (.*)\s+ISBN: (.*)/ ) {
  my ($title, $author, $isbn) = ($1,$2,$3);
  $author =~ s/\.//g; # Remove full stops
  print "<$title><$author><$isbn>";
  # Do more stuff...
}
[download]

$;=sub{$/};@;=map{my($a,$b)=($_,$;);$;=sub{$a.$b->()}}
split//,".rekcah lreP rehtona tsuJ";$\=$ ;->();print$/
[download]