Comprehensive lists of notable unsolved cryptograms are available here:
In our talk Famous and Not-So-Famous Unsolved Cryptograms, we cover the following crypto mysteries:
The Henry Dobosnys murder case
Codebreaking: A Practical Guide
The new book in December 2020 by Elonka Dunin and Klaus Schmeh
Comprehensive lists of notable unsolved cryptograms are available here:
In our talk Famous and Not-So-Famous Unsolved Cryptograms, we cover the following crypto mysteries:
The Henry Dobosnys murder case