dentro de body



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var NETS=navigator.userAgent.indexOf("Netscape");
var OPER=navigator.userAgent.indexOf("Opera");
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document.write("<BGSOUND SRC=sound.mid LOOP=INFINITE>");
} else {
document.write("<EMBED SRC=sound.mid AUTOSTART=TRUE ");
document.write("HIDDEN=true VOLUME=100 LOOP=TRUE>");
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