a = 2 
var slump = Math.random();
var talet = Math.round(slump * (a-1))+1;

if (talet==1) 
{
document.write('<a href="http://www.leadge.com/pmcourse/" target="_blank"><img src="/advertisement/pm2007468X60.gif" border="0"></a>');
}
if (talet==2) 
{
document.write('<a href="http://www.leadge.com/pmcourse/" target="_blank"><img src="/advertisement/pm2007468X60.gif" border="0"></a>');
}