Status Updates From The Complete Tolkien Companion

Fun fact not in this book: the "hero prop" (main on-screen prop) of Bilbo and Frodo's sword Sting is owned by Tolkien superfan and LOTR expert Stephen Colbert.

My only small gripe with this book is that I wish it gave the name of the work(s) the entry was drawn from. I realize that there are so many editions of Tolkien's books that you couldn't say "The Two Towers, p.185" but knowing the book would help. I also realize that this book is already massive, and citing scenes ("where Aragon is speaking to Boromir about blah blah") is impractical bloat.

I was gifted a copy of this as a teenager, when I first read LOTR. No idea whatever became of it, but I cherished it. A handy reference, and now I own a new copy.

This is where Goodreads breaks down. I will read all of this book, undoubtedly. But not in a linear fashion. It's essentially a book of footnotes and reminders, to consult as needed. How do you document progress in that?