O'Connor, J. J., and Robertson, E. F., "Dimitri Fedorovich Egorov," MacTutor. January 2012. FRetrieved 11 August 2020.
zbmath.org
He published a proof of this theorem in the short paper Egoroff 1911, and the result become widely acknowledged under his name. Carlo Severini had published a proof of the same result a year before, in the paper Severini 1910; however, the work of Severini was unnoticed until Leonida Tonelli recalled attention on it (see the entry about Carlo Severini for further details). Severini, C. (1910), "Sulle successioni di funzioni ortogonali (On the sequences of orthogonal functions)", Atti dell'Accademia Gioenia, serie 5a (in Italian), 3 (5): Memoria XIII, 1–7, JFM41.0475.04.