Penso che l'ultimo url che hai messo (http://www.w3.org/TR/html4/loose.dtd) vada messoOriginariamente inviato da cicciofarmaco
concodice:<?xml version="1.0" encoding="iso-8859-1"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml">codice:<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" http://www.w3.org/TR/html4/loose.dtd>
tra le doppie apici: ("http://www.w3.org/TR/html4/loose.dtd")