I found the decision in the forum:
...components/com_abook/models/search.php, line 250:
Code: [Select]
// $query->order($db->escape($this->getState('list.ordering', 'a.ordering')).' '.$db->escape($this->getState('list.direction', 'ASC')).', a.title');
// commented out and for instance new:
$query->order($db->escape('a.year DESC'));
$query->order($db->escape('a.pag_index'));
This works! Thanks!