/**
  * Get contributors of wiki
  */
 function getContributors()
 {
     include_once "./Modules/Wiki/classes/class.ilWikiPage.php";
     $contributors = ilWikiPage::getParentObjectContributors($this->wiki_id);
     $this->setDefaultOrderField("lastname");
     $this->setDefaultOrderDirection("asc");
     $this->setData($contributors);
 }