I’m currently trying to work on my portrait drawings, and this is a good starter book with very specific, user-friendly instructions on how to draw faces.
Within a matter of days, you can easily learn the fundamentals; sure, you have to practice your face drawings over time, but this is a great start to people interested in learning how to draw.
For me, what I like about this book is that it emphasizes starting, from drawing using simple skills and using pre-existing pictures. I am not a natural artist (people start somewhere), and this book gives specific steps on, how to, lets say, draw an eye, using basic measurements and shading.
For pictures, see Parka Blogs.