E Klussmann (1843) MJ Berchem (1861) D de Moor (1877) Theodor Mommsen, , bk. iii, ch. 24. V. Crivellari, (1889). (On Virgil's indebtedness to Naevius and Ennius.) Thelma B. De Graff, , New York, 1931. Barchiesi (M.), , Padoue, 1962. ID., , Pise, 1978.