It was narrated from Abu Hurairah that:The Prophet said: "Do not let the Bedouins make you change the name of your prayer." Ibn Harmalah added: "Rather it is the 'Isha', but they say the 'Atamah because they bring their camels in for milking at that time (when it is dark)
Hadith No. 705
Sunan Ibn Majah
Gradings:
Al-Albani:
Hasan Sahih
Muhammad Fouad Abd al-Baqi:
Hasan Sahih
Zubair Ali Zai:
Hasan