Waddell, V.G. and Milinkovitch, M.C. and Bérubé, M. and Stanhope, M.J. Molecular Phylogenetic Examination of the Delphinoidea Trichotomy: Congruent Evidence from Three Nuclear Loci Indicates That Porpoises (Phocoenidae) Share a More Recent Common Ancestry with White Whales (Monodontidae) Than They Do with True Dolphins (Delphinidae). Molecular Phylogenetics and Evolution. 2000, 15 (2): 314–318. PMID 10837160. doi:10.1006/mpev.1999.0751.
Bianucci, Pesci, Collareta, and Tinelli. A new Monodontidae (Cetacea, Delphinoidea) from the lower Pliocene of Italy supports a warm-water origin for narwhals and white whales. Journal of Vertebrate Palentology. 2019.
Jorge Vélez-Juarbe and Nicholas D. Pyenson. Bohaskaia monodontoides, a new monodontid (Cetacea, Odontoceti, Delphinoidea) from the Pliocene of the western North Atlantic Ocean. Journal of Vertebrate Paleontology. 2012, 32 (2): 476–484. doi:10.1080/02724634.2012.641705.