code: public function getHyperlink($pCellCoordinate)
      {
          // return hyperlink if we already have one
          if (isset($this->hyperlinkCollection[$pCellCoordinate])) {
              return $this->hyperlinkCollection[$pCellCoordinate];
          }
  
          // else create hyperlink
          $this->hyperlinkCollection[$pCellCoordinate] = new Hyperlink();
  
          return $this->hyperlinkCollection[$pCellCoordinate];
      }
docs: Get hyperlink.
  
  @param string $pCellCoordinate Cell coordinate to get hyperlink for, eg: 'A1'
  
  @return Hyperlink