I try to get references of a specific item using Podio's get_references method in PHP (https://developers.podio.com/doc/items/get-item-references-22439). Usually, when there's nothing to return, NULL is returned, but this time undefined is returned. My item exists and has references. I can access my item without problem.
I've also simulated the API request by Podio's doc and the returned result is also undefined.
Has someone already had this problem?