function popupwindow(valor)
{
if (valor==1) {window.open("textras/overviewgalaxytdbuildingGRE.html","","height=750,width=1051,menubar=0,resizable=0,scrollbars=0, status=0,titlebar=0,toolbar=0,left=100,top=100")}
if (valor==2) {window.open("textras/overviewgalaxytdbuildingGRE1.html","","height=629,width=920,menubar=0,resizable=0,scrollbars=0, status=0,titlebar=0,toolbar=0,left=100,top=100")}
if (valor==3) {window.open("textras/overviewgalaxytd.html","","height=702,width=738,menubar=0,resizable=0,scrollbars=0, status=0,titlebar=0,toolbar=0,left=100,top=100")}
if (valor==4) {window.open("textras/overviewgalaxyfeatureswindow1.html","","height=750,width=796,menubar=0,resizable=0,scrollbars=0, status=0,titlebar=0,toolbar=0,left=100,top=100")}
if (valor==5) {window.open("textras/overviewgalaxyfeatureswindow2.html","","height=632,width=725,menubar=0,resizable=0,scrollbars=0, status=0,titlebar=0,toolbar=0,left=100,top=100")}
if (valor==6) {window.open("textras/overviewgalaxyfeatureswindow3.html","","height=632,width=725,menubar=0,resizable=0,scrollbars=0, status=0,titlebar=0,toolbar=0,left=100,top=100")}

}