Musnad Ahmad 553:2

Yunus ibn Muhammad narrated to us, Shayban narrated to us, from Qatadah, who said: Anas ibn Malik narrated to us, that Malik ibn Sa'sa'ah narrated to them that the Prophet of Allah, peace and blessings of Allah be upon him, said: "While I was at the Ka'bah, between sleeping and being awake," and he mentioned the hadith. He said: "Then we set off to the seventh heaven, and Jibril asked for it to be opened. It was said: 'Who is this?' It was said: 'Jibril.' It was said: 'And who is with you?' He said: 'Muhammad.' It was said: 'Has he been sent for?' He said: 'Yes.' So it was opened for him. They said: 'Welcome to him, and what a blessed arrival he has arrived.' Then we came to Ibrahim. I said: 'Who is this?' Jibril said: 'This is your father, Ibrahim.' So I greeted him, and he said: 'Welcome to the righteous son and the righteous prophet.' Then the Lote Tree of the Utmost Boundary (Sidrat al-Muntaha) was raised for me, and its leaves were like the ears of elephants, and its fruits were like the jars of Hajar. And there were four rivers emerging from its base: two apparent and two hidden. I said: 'What is this, O Jibril?' He said: 'As for the two apparent ones, they are the Nile and the Euphrates, and as for the two hidden ones, they are two rivers in Paradise.' He said: 'Then I was brought two vessels, one containing wine and the other milk.' He said: 'So I took the milk.' Jibril said: 'You have attained the natural state (Fitrah).'"