function pageNav(target,sTag){
 
 	var tagAr = sTag.split('_');
	var s = parseInt(tagAr[1]);
	
	var idName = tagAr[0];

	if(target == 'next'){
		var	goId = s + 1;
	}else{
		var	goId = s - 1;
	}

	var go2File = document.getElementById(idName + '_' + goId).href;

	window.location= go2File;
 }