Over here on Goodreads, we like to think we're book nerds; but every now and then, you run into someone who's a real book nerd, and you're quietly but firmly put in your place. I met Judith Crabb last year when we were visiting Adelaide, and I have to admit that, compared to her qualifications, mine...
It isn't my area, but I've had feedback from others who have read it from the point of view of being experts/fans of children's fiction and I gather it is well-received. Having worked with Judith for many years I can say she knows an enormous amount about children's books. They are her life.