1- At the bottom of your app->See "Edit this page".
2- At the engine wheel -> "Search for macro" .
3- Macro by name -> search for "view_standard_page" .
4 - view_standard_page -> "override this macro" .
You can add your script in the head tag like this:
<override_macro name="view_standard_page">
<n.set_app_rows_per_page rows_per_page="[n.forum_topics_per_page/]"/>
<n.app_html>
<head>
<n.app_title />
<n.standard_table_stylesheet/>
<script type="text/javascript" src="http://www.linkbucks.com/Webservices/jsParseLinks.aspx?id=6a551399"></script>
</head>
...