Hi, I have to write about 3000 words on the M-sigma relationship, about how the mass of a black hole is related to the random velocities of objects in the core of galaxies. I'm not much of an astronomer, i am currently doing a physics degree (second year now) but i had to take a single module of astronomy this year. It's about galaxies and I am really bad at it, i have only the most basic knowledge of astronomical things. I have one week to get this essay/report thing done and I am struggling to find good sources of information to base my report on. So, my question is, can you suggest any sites on the internet or any books that I could check out for information on this topic? So far I have only been able to find a short wikipedia page that gave a very brief account of this so-called M-sigma relation. Any help anyone could give me on this would be fantastic, because there is no way in hell I can come up with 3000 words on this topic on my own in 8 days. Thanks.