сделал так
[CODE]
$arSelect = Array("NAME", "PROPERTY_AUTHOR", "DETAIL_PAGE_URL");
$arFilter = Array("IBLOCK_ID"=>42, "SECTION_ID"=>$bItem[ID]);
$res = CIBlockElement::GetList(Array("left_margin"=>"desc"), $arFilter, false, Array("nPageSize"=>1), $arSelect);
while($ob = $res->GetNextElement()){
$arFields = $ob->GetFields();
}
[/CODE]
мож кому пригодится