Musnad Ahmad 788:205

Yahya ibn Adam narrated to us, Sharik narrated to us, from Yazid ibn Abi Ziyad, from Abd al-Rahman ibn Abi Layla, from Abu Musa, from the Prophet, peace and blessings of Allah be upon him, who said: "He is not of us who shaves (the hair in grief), tears (the garment in grief), and raises the voice (in wailing)."