diff --git a/src/devices/wifi/dca-txop.h b/src/devices/wifi/dca-txop.h
index 7765520b2..55a4f2106 100644
--- a/src/devices/wifi/dca-txop.h
+++ b/src/devices/wifi/dca-txop.h
@@ -115,6 +115,9 @@ private:
   friend class TransmissionListener;
   friend class WifiRemoteStation;
 
+  DcaTxop &operator = (const DcaTxop &);
+  DcaTxop (const DcaTxop &o);
+
   // Inherited from ns3::Object
   Ptr<MacLow> Low (void);