Uchman A., Mikulas R., Housa V. (2003) The trace fossil Chondrites in Uppermost Jurassic–Lower Cretaceous deep cavity fills from the Western Carpathians (Czech Republic) // Geologica Carpathica. V. 54. N. 3. Pp. 181-187.
Uhlig V. (1910) Himalayan fossils. The Fauna of the Spiti Shales. Ser. 15. V. 4. N. 2. Pp/ 133-306, pls. 19-48, 77-91.
Usher J. (1952). Ammonite faunas of the Upper Cretaceous rocks of Vancouver Island, British Columbia. Geological Survey of Canada, Bulletin 21, 182 p.