private function _writeStyle()
	{
		$record    = 0x0293;   // Record identifier
		$length    = 0x0004;   // Bytes to follow

		$ixfe      = 0x8000;  // Index to cell style XF
		$BuiltIn   = 0x00;     // Built-in style
		$iLevel    = 0xff;     // Outline style level

		$header    = pack("vv",  $record, $length);
		$data      = pack("vCC", $ixfe, $BuiltIn, $iLevel);
		$this->_append($header . $data);
	}