private function determineSuperfluous($mentionedAuthors, $wantedAuthors, $path)
    {
        $superfluous = [];
        foreach (\array_diff_key($mentionedAuthors, $wantedAuthors) as $key => $author) {
            if (!$this->config->isCopyLeftAuthor($author, $path)) {
                $superfluous[$key] = $author;
            }
        }

        return $superfluous;
    }