[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}(\.[0-9]+)?(Z|[\+\-][0-9]{2}:[0-9]{2})?(/[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}(\.[0-9]+)?(Z|[\+\-][0-9]{2}:[0-9]{2})|) (ftp|http)s?://.* GET POST 0 1 dc:publisher dc:date georss:where dc:publisher dc:date georss:where An atom:feed must have an atom:author unless all of its atom:entry children have an atom:author. An atom:feed must have an atom:category with the OWC specification reference identified with the @scheme='http://www.opengis.net/spec/owc/specReference' An atom:entry must have one atom:content MUST have content element in a format understandable by generic Atom readers ( @type equal to 'html' is recommended) An atom:entry must have at least one atom:link element with a rel attribute of 'alternate' or an atom:content. An atom:entry must have an atom:author if its feed does not.