php simpleXML_load_file

I want to read a external xml page to a wordpress page on my site.
I have removed the url temporary. Can someone help me how to implement this in wordpress

<?php
include ('render_xml_to_html.php');
$url = '..';

?>

					<?php
						if(function_exists('render_xml_data')){
							render_xml_data($url);
						}else{
							echo null;//allows the page to continue rendering
						}
					?>

<?php

function render_xml_data($url){

		$xml = simpleXML_load_file($url,"SimpleXMLElement",LIBXML_NOCDATA); ;
		foreach ($xml->CURSUSEXPORT ->CURSUSSEN -> CURSUS as $cursus) {
			echo '<div class="Cursus">'."\n";
			echo '<h3>'.$cursus->CU_TITEL.'</h3>'."\n";
			echo '<p><span class="category">Begin datum: </span>'.$cursus->CU_BEGINDATUM.'</p>'."\n";
			echo '<p><span class="category">Locatie </span>'.$cursus->CU_CURSUSLOCATIE.'</p>'."\n";
			echo '<p><span class="category">Maximun aantal plaatsen: </span>'.$cursus->CU_MAXIMUM_AANTAL_CURSISTEN.'</p>'."\n";
			echo '<p><span class="category">Aantal vrije plaatsen: </span>'.$cursus->CU_AANTAL_VRIJE_INSCHRIJVINGEN.'</p>'."\n";
			echo '<p><span class="category">Inschrijven: </span> voor cursus  '.$cursus->CU_TITEL.' Klik  <a href="https://nim.chainwisehosted.nl/extranet/modules/cursusplanner/cursusoverzichtcurr_popup.asp?Actionpl_Cursus=findHTML&Action=Nieuw&Titel_flt='.$cursus->CU_CURSUSCODE.'">Hier </a></p> </br>'."\n";
			echo '</div><!--end Cursus einde-->'."\n";
		}
	}
?>