I've read this a number of times in paper form. Nice to be able to read it on the iPad. This is very short though. In paper form it was always a thin booklet rather than a book per se. Seems like in the '70s it used to be under $2. Most pages showed a row of dashes or dots or both at the top of tbe page, which I found a bit distracting. I only noticed maybe three or so proofreading errors. Typography is okay. I'm glad it's in a sans-serif font. One minor point is that the book seems to be saying, if I understood correctly, that whenever someone groans in the Spirit in prayer, that it's always intercession for the lost. That is clearly incorrect.