/**
  * The url which is used to fetch the data of a worksheet as a list
  *
  * @return string
  */
 public function getListFeedUrl()
 {
     // return Util::getLinkHref($this->xml, 'http://schemas.google.com/spreadsheets/2006#listfeed');
     # added by @aravindanve
     return Util::getContentHref($this->xml);
 }
 /**
  * Returns the feed url of the spreadsheet
  * 
  * @return string
  */
 public function getWorksheetsFeedUrl()
 {
     // return Util::getLinkHref($this->xml, self::REL_WORKSHEETS_FEED);
     # added by @aravindanve
     return Util::getContentHref($this->xml);
 }