http://book.klll.cc/ebooks/subject/20094.opds 2025-08-28T04:34:59Z Books about Fortification (sorted by popularity) Free eBooks since 1971. Project Gutenberg https://book.klll.cc webmaster@gutenberg.org https://book.klll.cc/gutenberg/favicon.ico 25 1 2025-08-28T04:34:59Z https://book.klll.cc/ebooks/33491.opds Die Festungen gegenüber den gezogenen Geschützen (German) M. von Prittwitz