German, English, Divers (2017)
The booklet describes the history and development of what was the most impressive fortification built in the Eastern part of the German Empire, near what is now called Grudziadz in Poland (then: Graudenz).
Polish, Paperback (2015)
Truely BEAUTIFUL book about the fortifications of Malbork in Poland (German name: Marienburg). The book describes ca. 150 fortifications.