Yahya related to me from Malik from Abdullah ibn Abi Bakr ibn Amribn Hazm that he had heard Abbad ibn Tamim say that he had heardAbdullah ibn Zayd al-Mazini say, "The Messenger of Allah, may Allahbless him and grant him peace, came out to the place of prayer andasked for rain, and when he faced the qibla he turned his cloak insideout."Malik was asked how many rakas there were in the prayerof asking for rain and he said, "Two rakas, and the imam does theprayer before he gives the khutba. He prays two rakas, and then hegives a khutba and makes dua, facing the qibla and turning his cloakinside out. He recites out loud in both rakas, and when he turns hiscloak inside out he puts what is on his right on his left, and what ison his left on his right, and all the people turn their cloaks insideout when the imam does so, and face the qibla, sitting."
USC-MSA web (English) reference: Book 13, Hadith 1
Arabic reference: Book 13, Hadith 452