Homodyne network analyzer with cascaded digital phase shifters. - Uwe Gaertner; Burkhard Schiek; Olaf Ostwald (Proc. IEEE, 1986)

History and Modern Cryptanalysis of Enigma's Pluggable Reflector. - Olaf Ostwald; Frode Weierud (Cryptologia, 2016)

Modern breaking of Enigma ciphertexts. - Olaf Ostwald; Frode Weierud (Cryptologia, 2017)

Modern cryptanalysis of the Truppenschlüssel. - Olaf Ostwald; Frode Weierud (Cryptologia, 2023)