The original book has now been published in English

The book "The Ninth Day" was based on "Pfarrerblock 25487," a diary-like memoir by Fr. Jean Bernard. That book has now been published in English for the first time.

The new English translation is entitled "Priestblock 25487: A Memoir of Dachau".

It is a short, but compelling work. Quite engaging. The author is a very good writer: he knows how to sketch a scene with just sufficient detail to bring it and the characters to life. Although his style is simple, it is quite vivid, and captures a range of human emotions. I thoroughly enjoyed the book, and think it's comparable in literary merit and historical interest to other notable Nazi camp memoirs like Elie Wiesel's "Night" and Primo Levi's "Survival in Auschwitz".

I think anyone who enjoyed the film would probably like the book, also. It's available at Amazon:
http://www.amazon.com/Priestblock-25487-Memoir-Jean-Bernard/dp/0972598170

The movie clearly took many liberties with the book's story. Nonetheless, I think those deviations from the original text remain authentically in the spirit of the text.

In sum, "Priestblock 25487: A Memoir of Dachau," is a great read. I highly recommend it.