Parisi, I. “A Borrowed Cipher for a Top-Secret Letter Written by Frederick of Aragon King of Naples to the Catholic Kings in the BnF, Espagnol 318”. Studi Di Storia Medioevale E Di Diplomatica - Nuova Serie, no. 4, Nov. 2020, pp. 157-7, doi:10.54103/2611-318X/14378.