Is this only for mass market trade books? There are dozens of university presses in North America alone that have a huge selection of high quality books avail

Is this only for mass market trade books? There are dozens of university presses in North America alone that have a huge selection of high quality books available for order at any time, from what I can see online. And there are multiple small distributors for the rest of the world that seemed to be viable businesses. For example, I bought an excellent textbook published by Kyoto university on morphology of modern agricultural products written by Japan's leading expert in this field, including relevant research notes from his best students, all bound in an excellent hardcover English translation.