Hadith 771:2
Waki’ narrated to us, Hisham al-Dastawa’i narrated to us, from al-Qasim ibn ‘Awf al-Shaybani, from Zayd ibn Arqam, who said: The Messenger of Allah (may Allah bless him and grant him peace) went out to the people of Quba’ while they were performing the Duha (forenoon) prayer. He said: "The prayer of the oft-repentant (al-awwabin) is when the young camels feel the heat of the sun from the forenoon."
حدثنا وكيع، حدثنا هشام الدستوائي، عن القاسم بن عوف الشيباني، عن زيد بن أرقم قال: خرج رسول الله صلى الله عليه وسلم على أهل قباء وهم يصلون الضحى فقال: " صلاة الأوابين إذا رمضت الفصال من الضحى "