var sca = 2;
var sa = new Array(sca);
    
    sa[0] = "http://airtravelcenter.ch/js/bwiz468.js";
    sa[1] = "http://airtravelcenter.ch/js/adcntrB.js";

    function pickRandoma(range) {
        if (Math.random)
            return Math.round(Math.random() * (range-1));
        else {
            var now = new Date();
            return (now.getTime() / 1000) % range;
        }
    }
    
        var choicea = pickRandoma(sca);
    document.writeln("<script src=" + sa[choicea] + ">" + "<" + "/script" + ">");