LSJ
ηκος, ὁ, ἡ, with beautiful helmet, AP 6.120 (Leon.).
with fine crest, ταὧς Babr. 65.1a.
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)
Pape
ηκος, schön gehelmt, Ἀθηναίη, Leon.Tar. 60 (VI.120).
Pape, Griechisch-deutsches Handwörterbuch (3. Aufl., 1914)