Remove doorknob lock with NO SCREWS showing

How to remove this door knob and plate with no obvious screws remove door knob no screws no slot I scratched my head many times trying to figure out how to get the latch and knob apart on this era of door hardware but after an hour of remove door knob no screws no slot There are no screws in the shank of the door knob The back plate can be popped loose, and does have some screws behind it, but you have to

texas slot 888 Depress a button with a paperclip or thin tool if there's no screw If you don't see a screw head inside the slot, straighten a paperclip or grab a thin,