function abrir(mypage, myname, w, h, scroll)

{

var winl = (screen.width - w) / 2;

var wint = (screen.height - h) / 2;

winprops = 'height='+h+',width='+w+',top='+wint+',left='+winl+',scrollbars='+scroll+',noresize'

win = window.open(mypage, myname, winprops)

}