diff --git a/cocoa/src/appkit.rs b/cocoa/src/appkit.rs
index 04cb253..cf16151 100644
--- a/cocoa/src/appkit.rs
+++ b/cocoa/src/appkit.rs
@@ -1049,7 +1049,7 @@ pub trait NSWindow: Sized {
     unsafe fn setIgnoresMouseEvents_(self, ignoreMouseEvents: BOOL);
     unsafe fn mouseLocationOutsideOfEventStream(self) -> NSPoint;
     unsafe fn setAcceptsMouseMovedEvents_(self, acceptMouseMovedEvents: BOOL);
-    unsafe fn windowNumberAtPoint_belowWindowWithWindowNumber_(self,
+    unsafe fn windowNumberAtPoint_belowWindowWithWindowNumber_(_: Self,
                                                                point: NSPoint,
                                                                windowNumber: NSInteger) -> NSInteger;
 
@@ -1618,10 +1618,10 @@ impl NSWindow for id {
         msg_send![self, setAcceptsMouseMovedEvents:acceptMouseMovedEvents]
     }
 
-    unsafe fn windowNumberAtPoint_belowWindowWithWindowNumber_(self,
+    unsafe fn windowNumberAtPoint_belowWindowWithWindowNumber_(_: Self,
                                                                point: NSPoint,
                                                                windowNumber: NSInteger) -> NSInteger {
-        msg_send![self, windowNumberAtPoint:point belowWindowWithWindowNumber:windowNumber]
+        msg_send![class!(NSWindow), windowNumberAtPoint:point belowWindowWithWindowNumber:windowNumber]
     }
 
     // Converting Coordinates