My goal is to make it so that there is an asterisk after the price.
ie: $36.98*

I have managed to do this without having a sale in place. However, if there is a sale, the asterisk becomes

$28.99
22% off*

The code I need to modify is:
zen_get_products_display_price((int)$_GET['products_id']) ;

I don't know how to get a . '*' . in there without it creating an error. My cache didn't pick anything up which is frustrating in itself. Can someone please help.

Thanks!