Lewis & Short

Ŭlū̆brae, ārum, f., a small town of Latium, by the Pontine Marshes, now Cisterna, Cic. Fam. 7, 18, 3; Hor. Ep. 1, 11, 30; Juv. 10, 102; Inscr. Orell. 121 sq.
Hence,

  1. A. Ŭlū̆brānus, a, um, adj., of or belonging to Ulubrœ, Ulubran: populus, the inhabitants of Ulubrœ, Cic. Fam. 7, 12, 2.
  2. B. Ŭlū̆brenses, ĭum, m., the inhabitants of Ulubrœ, the Ulubrans, Plin. 3, 5, 9, § 64.