Musnad Ahmad 937:208

Yahya ibn Sa'id narrated to us, from 'Abd al-Hamid ibn Ja'far, [who said]: Yazid ibn Abi Habib narrated to me, from Suwayd ibn Qays, from Mu'awiyah ibn Hudayj, from Abu Dharr, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "There is no Arabian horse but that it is granted permission at every dawn to make two supplications. It says: 'O Allah, You have placed me in the charge of whom You have placed me in the charge of among the children of Adam, so make me the most beloved of his family and his wealth to him,' or 'the most beloved of his family and his wealth to him.'" Abu 'Abd al-Rahman said: My father said: 'Amr ibn al-Harith differed from him, and said: From Yazid, from 'Abd al-Rahman ibn Shumasah. And Layth said: From Ibn Shumasah.