Euler's "Logogriph"

I heard of breaking of the cryptogram left by the Swiss mathematician Leonhard Euler at Klausis Krypto Kolumne. I compared the solution of the same cryptogram by two people: Pierre Speziali and Hans Rohrbach in a new article in Japanese "数学者オイラーの残した暗号文の解読" and mentioned the cryptogram in "Unsolved Historical Ciphers" (which also covers cryptograms that remained unsolved for some time).
Rohrbach's solution (1973) involves counting symbol frequencies with contact characteristics. So, I also mentioned it in the section "Contact Chart in the Days of Manual Work" in "Creating a Contact Chart with Microsoft Excel".