Mellokitty is correct.
However a paper written by Dr Michael Starks called Marijuana Chemistry, Genetics, Processing and Potency would be a great read. It was written before much of the medical cannabis literature took off and is a very informative piece of work.
It's a couple hundred pages long, like most "real" publications... however it's indexed and you can also use the search function in adobe to skip through what you'd perfer to read.
FYI I think the one full text version available for free on Google (the one I have) was scanned to text. So it has some noticable spelling error artifacts.... those probably weren't in the published paper.