Hello, sorry for the late reply to this question, I just saw this today. There is a book that I think you would be interested in, which covers the topic of mon. The book is titled Japanese Heraldry and Heraldic Flag , edited by David F. Phillips. A large portion of the book is dedicated to mon, providing general information behind the, different styles, types, etc. It also has a rather lengthy catalogue of different ones used throughout history, along with what each one represented and notable houses and/or clans that used them.