function pop_winpopup(strBrochure) {

    popup = "";

    if(popup){
        if(popup.closed){
            popup = window.open("http://www.pagedirect.nl/users/"+ strBrochure + "/pagedirect.html", "popup", "top=" + ((screen.availHeight/2) - (678 / 2)) + ",left=" + ((screen.availWidth/2) - (955 / 2)) + ",width=955,height=678,resizable=0,toolbar=0,scrollbars=0,location=0,status=0,menubar=0");
        } else { 
            popup.focus();
        }
    } else {
        popup = window.open("http://www.pagedirect.nl/users/"+ strBrochure + "/pagedirect.html", "popup", "top=" + ((screen.availHeight/2) - (678 / 2)) + ",left=" + ((screen.availWidth/2) - (955 / 2)) + ",width=955,height=678,resizable=0,toolbar=0,scrollbars=0,location=0,status=0,menubar=0");
    }
}