See the link for Imam Abu Bakr al-Jassas al-Hanafi’s famous early work on Hanafi usul al-fiqh.
http://www.archive.org/details/FSooL
Published by Bilal Ali
Bilal Ali is a student of the sacred Islamic sciences with a special interest in Hadith, Hanafi law, Behavioral Science, and Education. He currently serves in various capacities at Darul Qasim College, Khalil Center, Al-Mustafa Foundation, Masjid Uthman, and Usul Academy.
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Ṭaḥāwī 
Q. for Bilal Ali Ansari: What usul work have you found that impressively expresses both the early Hanafi scholars’ approach to usul vs the latter?
A good book that discusses the variations within the usul from even the early period is Doctor Haytham Khaznah’s “Tatawwur al-Fikr al-Usuli al-Hanafi” published by Dar al-Razi. I haven’t finished reading it but I somewhat recall its contents covering the topic in question.
Is he muthasila
Best edition on the market?