[Plugin: User Access Manager] Fatal error: Call-time pass-by-reference has been removed

I was unable to activate the plugin. When I try, I get the following error:

Fatal error: Call-time pass-by-reference has been removed in C:\wamp\www\localsite\wp-content\plugins\user-access-manager\class\UamUserGroup.class.php on line 646.

https://www.ads-software.com/extend/plugins/user-access-manager/