public function getPageClassOptions()
    {
        $options = [];
        
        foreach (ClassInfo::subclassesFor(Page::class) as $class) {
            
            $type = self::findByClass($class);
            
            if (!$type || $type->ID == $this->ID) {
                $options[$class] = Injector::inst()->get($class)->i18n_singular_name();
            }
            
        }
        
        asort($options);
        
        return $options;
    }