Which StorageDefinition (FieldType) for multiple entity autocomplete field?

Hi, I need to know, which type of storage definition I have to use, when i have an entity reference field. My code: (Focus on “tags”) FieldType Definition: public static function propertyDefinitions(StorageDefinition $storage) { $properties = []; $properties[‘quantity’] = DataDefinition::create(‘string’)->setLabel(t(‘Quantity’)); $properties[‘style’] = DataDefinition::create(‘string’)->setLabel(t(‘Style’)); //$properties[‘tags’] =[…]