Book recs for drawing people

I checked out the list of recs over on smmo and thought a few might be okay, but I'm kinda picky about books and wanted to cast out the net for a few more opinions. I'm looking for figure drawing/anatomy/portrait type books. If any of you have any suggestions I'd love to hear them (as well as what you liked about that book in particular; most comprehensive, easiest to understand, good examples/illustrations, etc). These books can get expensive so I'll probably try to get them from the library before I decide if they're a keeper, or used.

Thanks in advance!