Narrated Marwan bin Al-Hakam and Al-Miswar bin Makhrama:
When the delegates of the tribe of Hawazin after embracing Islam, came to Allah's Apostle, he got up. They appealed to him to return their properties and their...
O Allah, I ask You for the goodness of her and the goodness upon which You have created her, and I seek refuge in You from the evil of her and from the evil upon which You have created her.
Info: (If you purchase a camel then take hold of the top of its hump and say the same). Abu Dawud 2/248 and Ibn Majah 1/617. See also Al-Albani, Sahih Ibn Majah 1/324.