Sahih Bukhari

Narrated Usama bin Zaid:Allah's Messenger (ﷺ) proceeded from `Arafat and dismounted at the mountainous pass and then urinated and performed a light ablution. I said to him, ""(Shall we offer) the prayer?"" He replied, ""The prayer is ahead of you (i.e. at Al-Muzdalifa)."" When he came to Al-Muzdalifa, he performed a perfect ablution. Then Iqama for the prayer was pronounced and he offered the Maghrib prayer and then every person made his camel kneel at his place; and then Iqama for the prayer was pronounced and he offered the (`Isha') prayer and he did not offer any prayer in between them (i.e. Maghrib and `Isha' prayers)