document.write('<div id="footer-vdm"></div>');

textToDisplay = '<iframe width="960px" scrolling="no" height="59px" frameborder="0"';
textToDisplay += 'style="border: 0px none;" src="http://www.marseille.fr/sitevdm/footer.html">';
textToDisplay += '<p>Your browser does not support iframes.</p></iframe>';

document.getElementById('footer-vdm').innerHTML =textToDisplay;