I was in the library today. Luckily, I can find almost any book on amazon at my schools engineering library. I was looking for a controls book in the controls section. I checked it out with the intention of 'try before you buy'. But I noticed that for every one controls book there are about (not exaggerating) 20-30 IDENTICAL books on the topic. I dont mean somewhat the same, I mean they downright STOLE the size, content, and page layout. Grab any controls book and look at the last chapter. Its probably chapter 13 and its probably on the z-transform. That being said, do we REALLY need 20-30 sub-par copy-cat books? I think there are a lot of professors out there that dont have anything real to do, so they rehash good works, making them suck in the process. There are a FEW exceptions. I know one professor who wrote a controls book on campus that really is VERY different from anything out there. Its an amazing reference with new material and insights. But seriously.....................................stop putting out all this crap. Clausius was right, everyone including the garbage man seems to write a textbook these days. Big name competitors are: Statics/Dynamics is: Beer-Johnson Vs. Hibbeler Controls: Nise vs. Ogatta But if it were not bad enough that these 'big names' basically have the SAME book, there are 30x other people who rip off these books as well. So its a copy of a copy..... I'm willing to bet you there are similar examples in your field of study.