Is there a get for media by ReferenceID

Thanks, I have tried using listAction, but i can't get any response other than undefined ...

  var mycb = function(success, results) {
    if(!success) {
        console.log("failed:" + results);
    } else {
        console.log("passed:" + results);
    }

};
var res = client.media.listAction(mycb, filter, pager);

The callback gets a "success" but the result is undefined , so the output reads
passed: undefined