These are my books.
The second and the fourth are the Traditional Chinese versions of the first and the third respectively.
The English translations of the book names would be (if you don't read Chinese):
Operating System From Scratch (the first and the second)
Orange'S: The Implementation Of An Operating System (the third and the fourth)
Orange'S: The Implementation Of An Operating System is also known as the 2nd edition of Operating System From Scratch,
but it's more like a brand new book than a common second edition because it includes four more chapters and the book was re-typeset completely by myself
(I was not satisfied with the typeset of the 1st edition).
Furthermore, the OS introduced in Orange'S: The Implementation Of An Operating System is much more complicated than
that in Operating System From Scratch.