I heard a word "VT/R reference". I have been googling like a few hours. I could not find a solid lead. If you know what will be the best paper to understand the concept of vt/r reference. Please let me know.
I don't know which books you have access to but the R Jacob Baker "CMOS Circuit Design Layout and Simulation" covers it briefly in Chapter 23 - voltage references. I guess a lot of other books would as well. As it is not particularly stable it doesn't usually get a lot of space devoted to it. Beta multipliers tend to be more common.