Nonius Marcellus. Compendiosa doctrina. Emend. et adn. L. Müller. 2 vols. Leipzig, 1888.
Oberziner, G. Origine della plebe Romana. Leipzig and Genoa, 1901.
Obseq. = Iulii Obsequentis ab anno urbis conditae DV prodigiorum liber, (in) Weissenborn’s Livy, vol. xii. 193-209. 2d ed. Berlin, 1881.
Olcott, G. N. Thesaurus linguae Latinae epigraphicae, i. Rome, 1904-1908.
Oliver, E. H. Roman Economic Conditions to the Close of the Republic. Toronto, 1907.
Orelli and Baiter, Index legum Romanorum quarum apud Ciceronem eiusque scholiastas item apud Livium, Velleium Paterculum, A. Gellium nominatim mentio fit, (in their) Ciceronis Opera, viii. 3.
Oxyrhynchus Papiri. See Grenfell and Hunt; also Kornemann.
Pais, E. Storia di Roma, I. i, ii. Torino, 1898, 1899.
⸺ [Leg. of Rom. Hist.] Ancient Legends of Roman History. Translated from the Italian. New York, 1905.
⸺ Ancient Italy. Translated from the Italian by C. D. Curtis. Chicago and London, 1908.