What name did Enrico Fermi change it to in 1931?

In 1931, Enrico Fermi changed his name to "Enrico Fermi" as he became more prominent in the scientific community, though he was already known by that name prior to this year. It’s worth noting that he was born as Enrico Fermi in 1901 in Italy, and his name did not undergo any formal changes at that time. If you are referring to a specific event or context in 1931 related to his work or collaboration, please clarify for a more accurate answer.