Responses
I don't think it's wrong, just it may be that at that point it was decided to count the actual chapters, meaning that the chapters that were for exemple 30.1, 30.2, 30.3, all these three should theorically be chapter 30, but it was counted as three separated chapter.
My explanation is not exactly clear but hope it's understandable.
How did it go to 30 to 90???( ̄∇ ̄")