sub link_numbers ($$) {
   my $data = $_[0];
   my $link = $_[1];
   $data =~ s/([s]?s\. )?(\d+(?:\.\d+)?(?:\([^\)]+\))*)/<JL:ref2,\"$link $2\">$1$2<\/JL>/g;
   return $data;
}

while ($line = <DATA>) {
    $line =~ s/ ((?:(?:[s]?s\. )?\d+(?:\.\d+)?(?:\([^\)]+\))*(?:, | and | or )?)+)((?: of| the|,)+ )(<JL:ref2,\"([^\">]+)\">)/" " . link_numbers($1,$4) . "$2$3"/ge;
    print $line;
    print "\n";
}

__DATA__
This can be found in ss. 3 and 4 of the <JL:ref2,"Interpretation Act">Interpretation Act</JL>.
As discussed in s. 3 or 5 of the <JL:ref2,"Interpretation Act">Interpretation Act</JL>.
Filling up space in ss. 3, 4, 5, 6, 7 or 8 of the <JL:ref2,"Interpretation Act">Interpretation Act</JL> .