All this being said, I received yesterday the book The Art and Making of Dumbo and I was blown away by it. This is clearly one of the best "making of" art books that I have ever seen. The research that the author, Leah Gallo, conducted to write the text is breathtaking, the amount, quality and variety of illustrations is unparalleled, and the whole volume was clearly laid out by someone that is truly passionate about her subject matter.
What makes the book even more valuable from my standpoint, though, is the first chapter, which deals with the making of the original, animated movie. Like the rest of the book it is meticulously researched and represents the best history of the making of Dumbo that I have ever read to date, complete with very precise end-notes.
Sadly, the chapter contains a small mistake. A few years ago, in Walt's People - Volume 9, I re-released Mark Langer's interview with Ken O'Connor, complete with the introduction that Mark had written for its original publication in Animation Journal. Unfortunately, author Leah Gallo, when she read that introduction to the interview thought that I had written it and ended up quoting from it attributing the quote to me. You now know that the quote is from historian Mark Langer.
That being clarified, I really recommend Leah's book, especially if you enjoyed Tim Burton's movie.