Figure sketches

Some stuff from my sketchbook. I've been attending some life-drawing sessions for the first time and I have to say that I love it. It's definitely not the same that drawing from a picture.
I only wish we had some more time to draw the pose, but I can imagine how hard that must be for the model. Seriously, props to those guys!

These range from 5 - 30 minutes (I think the one on the top is like 40 mins, maybe).
 

P.S.: Oh, and the two faces are from photo references. The male one is from here: http://www.portrait-photos.org/photo/19499.html , and the female one from here: http://www.portrait-photos.org/photo/15788.html (Great site for portraits)