Problem Disabling Calendar Notifications

I could use some help with disabling notifications on my KitKat Galaxy S4.

I prefer a calendar application called Business Calendar over the built-in calendar application. I've disabled the built-in one, however it continues to send me notifications.

On Googles, I've configured calendar to not send notifications, but my phone doesn't seem to care either way.

I can no longer find the means of disabling notifications on the phone, which I swear was there at jelly bean or at lease ice cream sandwich.

Can someone describe how to disable these please?