Bulugh al-Maram #211

Narrated 'Abdullah bin Zaid bin Abd-Rabbihi (RA): A man appeared to me while I was asleep and told me to say, "Allahu Akbar, Allahu Akbar (Allah is the Most Great, Allah is the Most Great)" and he mentioned the Adhan with Allahu Akbar four times without Tarji', and the Iqama once except Qad qamat-is-Salah (the prayer stood ready to begin), (he repeated it twice). He ('Abdullah) said when it was morning I went to Allah's Messenger (ﷺ) and he said, "It is a true vision..." .