protected function bootstrapHeading($size, $content, $description, $class) {

        $sizes = [1, 2, 3, 4, 5, 6];

        $attributes = [];

        $attributes["class"] = [$class];

        $element   = "h" . (true === in_array($size, $sizes) ? $size : 1);
        $secondary = null !== $description ? " <small>" . $description . "</small>" : "";
        $innerHTML = (null !== $content ? $content : "") . $secondary;

        return static::coreHTMLElement($element, $innerHTML, $attributes);
    }