var total = 7;

var refs = [
"http://arctogaia.com/VTORZH/",
"http://www.arctogaia.com/public/putin.htm",
"http://www.arctogaia.com/public/templars/desiter.htm#voda",
"http://www.arctogaia.com/public/geo-new.htm",
"http://www.arctogaia.com/public/mistevr/mistevr4.htm",
"http://www.arctogaia.com/public/osoka.htm",
"http://www.arctogaia.com/public/txt-protiv.htm",
];


var rn = Math.random();
var ch = Math.floor(rn * total);
var ln = refs[ch];
document.writeln("<a href=\"" + ln + "\"><img src=\"http://arctogaia.com/java/a4/a" + (ch+1) + ".gif\" width=150 height=80 alt=\"\" border=\"0\"></a>");