German U-Boat Warfare Kriegsmarine Collection
Two Great E-books about German U-Boats and their History.
1.U-Boat Warfare The Evolution of the Wolf Pack
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Three complete U-Boat Ebooks in PDF File Format
1...U-Boats in Action E-BOOK
2...U-Boat Bases and Bunkers BOOK 1941/45 E-BOOK
3...7th U-Boat Flotill......