public function formula_validation( $section, $message, $source )
	{
		if ( ! $this->log ) return;
		$this->conformanceIssueWarning = true;
		$errorMessage = sprintf( "[formula] $message (Section %s - %s)", $section, $this->arrayToDescription( $source ) );
		$this->log->_announce( array( 'section' => $section, 'priority' => PEAR_LOG_WARNING, 'message' => $message, 'source' => $source ) );
		$this->log->warning( $errorMessage );
		if ( isset( $source['error'] ) )
		{
			throw FormulasException::withType( $source['error'], "formula", $errorMessage );
		}
		return $errorMessage;
	}