1. The SQRI method: A new method for the evaluation of visible resolution on a display;Barten;Proc. SID,1987
2. The truth is, as nice as these TVs are, you probably will not see much difference. A 60-in. 4K will not look dramatically better than the 1080 p TV you have in your home right now unless you shove your nose up against the screen. The average person's eyes cannot see the difference when sitting 10 ft. away from a 60-in. TV. http://www.wired.com/gadgetlab/2013/01/the-4k-push-ces-2013/
3. Why Ultra HD 4K TVs are still stupid http://reviews.cnet.com/8301-33199_7-57566079-221/why-ultra-hd-4k-tvs-are-still-stupid/