Musnad Ahmad 330:3

Zayd ibn al-Hubab Abu al-Husayn al-Ukli narrated to us, he said: Abu Sahl Muhammad ibn Amr informed me, he said: Abdullah ibn Muhammad ibn Zayd informed me, from his paternal uncle Abdullah ibn Zayd, the one who saw the Adhan [in a dream], he said: So I came to the Messenger of Allah, may Allah bless him and grant him peace, and I informed him. He said: "Cast it upon Bilal." So I cast it upon him, and he gave the Adhan. He said: Then he [Bilal] wanted to give the Iqamah, so I said: "O Messenger of Allah, I am the one who saw it, and I want to give the Iqamah." He said: "Then you give the Iqamah." So he [Abdullah] gave the Iqamah, and Bilal gave the Adhan.