Catalog api type filter error: Type must be an array

Using  /api-browser/#!/learn/Catalogue/Catalogue_learn_v1_catalog, I use “type” dropdown

Producing this url:

learn/v1/catalog?page_size=20&show_item_list=1&type=elearning&assigned=1

I get this error :

 

"name": "Bad Request", "message": [ "Type must be an array" ], "code": 1002, "status": 400 }

I tried, using PostMan, various values simulating an array e.g. [“elearning”]

...but all attempts failed with same error.

What is the format to use for “type” filter?