function callHeader( $params )
    {
        $options = array();

        if ( isset( $params['size'] ) )
        {
            $options['fontSize'] = $params['size'];
        }

        if ( isset( $params['justification'] ) )
        {
            $options['justification'] = $params['justification'];
        }

        if ( isset( $params['fontName'] ) )
        {
            $options['fontName'] = 'lib/ezpdf/classes/fonts/'. $params['fontName'];
        }

        $this->addToPreStack( $options );

        $label = $params['label'];
        $level = $params['level'];

        return '<C:callInsertTOC:'. $label .','. $level .'>';
    }