Does the $agent->links method, as found in the WWW::Mechanize documentation not work for you?

my @links = grep {$_->text /$pattern/i} $agent->links();

for (@links) {
  storeurl( $_->url, $trackname, $year );
};
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I suggest that you read the WWW::Mechanize documentation, as it contains many helpfull hints about what is possible with WWW::Mechanize.