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+# pdf
+
+This folder contains the programs to build a book version of the 12 characters.
+
+## Installation
+
+1. [Install docker](https://www.digitalocean.com/community/tutorials/how-to-install-and-use-docker-on-ubuntu-16-04)
+
+## Create PDFs
+
+To build all PDFs, run
+
+```
+./build.sh
+```
+
+To build a specific PDF e.g. for English `en`, run
+
+```
+./build.sh en
+```
+
+The results will be present in the `books` folder.
+
+This uses the languages in the [play] folder.
+If you wonder why there is only English, pull the translations
+as describes in the [play] folder.
+
+[play]: ../play