For this, you should study Namaz-e-Ahnaf written by Mufti Habibur Rahman Qasmi Allahabdi. This book consists of evidences from the Quran, Hadith and traditions of Sahaba in detail. It has been published from Maktaba Rahmania, Azampur, Mau Aimah, Allahabad UP and is available on Deoband book depots.
Allah (Subhana Wa Ta’ala) knows Best
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