Hi all, Suppose I want to refer to chapter 1 and chapter 2 of a book. I may have (a) In chapters 1 and 2, the author... (b) In chapter 1 and 2, the author... I guess (a) is correct, right? Then suppose I want to refer to three or more chapters using "-". I may have (c) In chapters 1-3, the author... (d) In chapter 1-3, the author... I think I saw people using (d) rather than (c), but I am not sure. Can someone explain to me?