00580cam a2200193 4500 1851385350 TxAuBib 20250111120000.0 250109s2025||||||||||||||||||||||||eng|u 75074 Project Gutenberg PGUSA eng TxAuBib Gaines, Helen. Elementary cryptanalysis [Gutenberg] / Helen Gaines. Project Gutenberg, 2025. Project Gutenberg ; 75074 Public domain in the USA. Text. Project Gutenberg ; 75074. http://www.gutenberg.org/ebooks/75074