al-Khilaafiyyah Bayna Imaamayn Ash-Shafi'i wa Abee Hanifa wa Ashaabhu. This book highlights the main differences in fiqh rulings between Imaam Abu Hanifa and Imaam Ash-Shafi'i. Printed in 8 Volumes with Tashkeel on each and every letter! Al-Khilaafiyaat was written by al-Imaam al-Bayhaaqee (Rahimahullaah), In My Opinon it is one of the Best Books that I have come across that specifically deals with the difference of opinion among these two great Imaams (May Allaah be Pleased with both of them).