var oUl12_3=document.getElementById('ul12_3');
var aA12_3=oUl12_3.getElementsByTagName('a');

for (var i=0; i < aA12_3.length ; i++)
{
    aA12_3[i].onclick=function()
    {
        oUl12_3.removeChild(this.parentNode);
    }
}