Begat, A. & Kriwet, J. & Gelfo, J.N. & Cavalli, S.G. & Schultz, J.A. & Martin, T. (2023)
The first southern hemisphere occurrence of the extinct Cretaceous sclerorhynchoid sawfish Ptychotrygon (Chondrichthyes, Batoidea), with a review of Ptychotrygon taxonomy. Journal of Vertebrate Paleontology, 42(2), Article e2162411
DOI: 10.1080/02724634.2022.2162411

Kriwet, J. & Nunn, E.V. & Klug, S. (2009)
Neoselachians (Chondrichthyes, Elasmobranchii) from the Lower and lower Upper Cretaceous of north-eastern Spain. Zoological Journal of the Linnean Society, 155(2), 316–347
DOI: 10.1111/j.1096-3642.2008.00439.x

Mendiola, C. & Martinez, J. (2003)
La ictiofauna fósil (Chondrichthyes, Euselachii) del Mesozoico y Cenozoico de España. Revista de la Societat Paleontológica d'Elx, 9, 1–103

Bernárdez, E. (2002)
Los dientes de seláceos del Cretácico de la depresión central asturiana. Thèse Doct., Univ. d'Oviedo (non publiée): 1–476, 110 fig., 1–79 pl.

Kriwet, J. (1999)
Ptychotrygon geyeri n. sp. (Chondrichthyes, Rajiformes) from the Utrillas Formation (upper Albian) of the central Iberian Ranges (East-Spain). Profil, 16: 337–346