Variable-length Numerical Code in Austrian Archives

Given a ciphertext in digits continuously written without a break, its deciphering requires breaking the stream of digits into individual code groups. Although various schemes to allow it have been known for Italian ciphers, I noticed more elaborate schemes are documented in the Austrian archives, which are described in my new article, "Variable-Length Numerical Code in Austrian Archives". Some undeciphered ciphertexts (probably of a more basic type) are also presented.