"Shirobako Setting Material Collection" by P.A. Works. This is a very comprehensive collection of background materials related to Shirobako. Similar books exist for other series, but only this one comes with the level of introspection that is unique to Shirobako. This is the making of the anime that is about the making of anime.
The book is divided in six sections: character design, art design, props and miscellaneous objects, extra data for the anime series inside this series, interviews, and credits for every episode. Every bit of detail is covered, including lots of shelves where additional settings material are kept. There are surprising amount of detail and anime related in-jokes that might be overlooked while lots of actions were happening on screen, and it's much easier to appreciate these details in printed form.
In addition to the graphical material, there are lots of back stories to be found in the interviews section. I particularly liked the interviews with the production assistants describe how demanding the job was, and how this anime is well received with other people in the same industry. It has been very meta from beginning to end.
Meta jokes aside, reading this book totally makes you want to watch the series again to see how each micro design decision affected the big picture. It's more than 400 pages of full color materials, and every page is worth reading.
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