Musnad Abu Ya'la al-Mawsili 243:37

Abu Kurayb narrated to us, Yahya ibn Burayd narrated to us, my father narrated to me, from Abu Burdah, from Abu Musa, who said: He arrived at Umar’s [house] and stood at his door and said, "Peace be upon you and the mercy of Allah. Is permission granted for Abu Musa, or for Abdullah ibn Qays?" [He said this] three times, but he was not spoken to, so he turned away. Umar came out and said, "Where is Abu Musa?" They said, "He turned away." So he sent [someone] in his pursuit. When he came, he said, "What turned you away?" He said, "I asked for permission three times and was not granted permission, so I turned away. And I heard the Messenger of Allah (peace and blessings of Allah be upon him) say: 'Whoever asks for permission three times and is not granted permission, let him turn away.'" He said, "Bring me someone with you who heard this from him." He went to the Ansar and informed them. He said, "All of them said: 'We have heard it.'" He said, "Let some of you stand with me." So some of them stood with him and came to Umar and informed him.