García-Amorós, M. "George Seferis' Youth through His Correspondence with His Sister Ioanna Seferiadi: 1919-1924". Erytheia: Revista de Estudios Bizantinos y Neogriegos 36 (2015): 207-230.
https://dialnet.unirioja.es/servlet/revista?codigo=6156
https://www.hispanohelenica.org/publicaciones-achh/revista-erytheia/