Steve, thanks a million.
I'll give my tcl for future reference:
# /packages/edit-this-page/templates/article-index.tcl
#etp::get_page_attributes
etp::get_content_items
etp::get_content_items -package_id 978 -result_name topics
template::multirow foreach topics {
set url [site_node::get_url_from_object_id -object_id 978]${url}
append content "<a href=\"$url\"> $title </a> <br>"