The first study is about cry it out techniques, which have nothing to do with controlled crying at all. It is nowhere near the same thing, with cc you still go in as often as every minute to pat your baby on the bum so they know you are there etc. you just don't pick them up.
The second takes information from studies done as far back as 1976 and the latest is done in 2000. It also says that the studies used are not specifically for control crying as there have not been any studies undertaken on control crying at that point in time.
The link I posted is the closest thing to a study that anyone has done at this point.