Imam Muhammad bin Ishaq (may Allah have mercy on him) narrates, through Abdullah bin Muhammad bin Aqil (may Allah have mercy on him), from Muhammad bin al-Hanafiyyah (may Allah have mercy on him), from Sayyiduna Mu'awiyah (may Allah be pleased with him), who said: I heard the Messenger of Allah (peace and blessings be upon him) say: "Umra is valid."
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 16783