As mentioned in the other review, mine's the version published by Apple Press and Book Depository is selling it at the lowest price that I know of online.
This book is essentially a book of ideas, tips and techniques. The text for each tip is quite brief though and there are no step-by-step instructions. The book provides you with the idea and techniques and invites you to experiment and explore. It's a good book to refer back to for inspiration.
If you want to get really good at sketching people, I would also recommend Lynne Chapman's book called Sketching People: An Urban Sketcher's Manual to Drawing Figures and Faces which I feel is more informative.
There are two publishers for the book, Firefly Books and Apple Press. Price will differ depend on who and where you get it from.
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