Aam Aadmi Party rebel leader Yogendra Yadav on Saturday reacted to the show-cause notice issued to him by his party on Friday and called it a joke. The party on Friday issued show-cause notices to rebel leaders Yadav and Prashant Bhushan for alleged anti-party activities, taking the final steps towards their expulsion, even as Yadav questioned the move saying it was against the principle of natural justice. AAP spokesperson Deepak Bajpai said separate notices have been issued to Yadav, Bhushan, Anand Kumar and Ajit Jha, detailing out a list of charges against them, backed with evidence.