If you are a student or researcher using marfat.com books as a source, proper citation is crucial. Since the site does not always display publication dates, use this template (Chicago Style):
The core mission of Marfat.com is to digitize rare and out-of-print Islamic books, making them freely available to the public. For scholars in regions like Pakistan, India, Bangladesh, and the Middle East, as well as the diaspora in the UK, USA, and Canada, serve as a critical link to their intellectual heritage. marfat.com books
You don’t need the full title. Searching "Rehman" will pull up all books containing that word, such as Fayous-ul-Rehman . If you are a student or researcher using marfat