I have Mona's book. While I think it's good, I've had such great luck
with Drawing on the Right Side of the Brain that I feel no need for any
other drawing method. My kids really learn to draw using those
techniques. I remember how much it helped me once. It's an amazing book,
and I love the way they break drawing down into something they can really
understand. No reason you couldn't use some from each, though.