If you are looking for the specific books (which are famous for their "natural" weight distribution and realistic anime-style anatomy), they are widely available here:
Before you click that suspicious link or torrent, let’s dive deep into what this book actually offers, why it is invaluable, and the legitimate (and ethical) ways to access it for free or low cost.
Staff-wielding, floating, and "magical girl" transformation poses.
Review the poses before your session. Familiarize yourself with the "go-to" poses that fit your style.
If your search for the comes up empty, do not despair. These alternatives are either cheap or already free:
If you use this popular illustration software, it includes fully customizable 3D male and female models that you can pose directly on your canvas. 3. Public Domain and Archive Resources
Relying solely on your imagination or generic search engine images often leads to flat, lifeless drawings. Specialized pose books solve several critical technical problems: 1. Mastering Extreme Foreshortening