Hanks, Patrick; Hardcastle, Kate; Hodges, Flavia (2006), "Evelyn", A Dictionary of First Names, Oxford Paperback Reference (2nd ed.), Oxford University Press, p. 347, ISBN978-0-19-861060-1.
dil.ie
eDIL s.v. oíb: "semblance, appearance, aspect, nature or condition (of things or abstracts)"; "beauty or attractiveness (of appearance, nature or disposition)".