onclick="window.open('popup.html', '', 'width=350,height=500'); return false;"

onclick="window.open('popup.html', '', 'width=350,height=500,scrollbars=yes'); return false;

onclick="window.open('popup.html', '', 'width=350,height=500,scrollbars=yes,resizable=yes'); return false;

onclick="window.open('popup.html', '', 'width=350,height=500,scrollbars=yes,resizable=yes,toolbar=yes'); return false;