Einarson, Benedict (1967). "Notes on the development of the Greek alphabet". Classical Philology. 62: 1–24, especially p.13 and 22. doi:10.1086/365183. S2CID161310875.
Einarson, Benedict (1967). "Notes on the development of the Greek alphabet". Classical Philology. 62: 1–24, especially p.13 and 22. doi:10.1086/365183. S2CID161310875.