Musannaf Ibn Abi Shayba 3:4979

Abu Bakr narrated to us, he said: Abdullah ibn Numayr and Abu Usamah narrated to us, they said: Ubaydullah ibn Umar narrated to us, from Nafi’, from Ibn Umar, he said: Do not seek the time of the rising of the sun nor its setting for prayer, for the Messenger of Allah, may Allah bless him and grant him peace, used to forbid that.