Pereira A, Harris D, Tyack P, Matias L. Fin whale acoustic presence and song characteristics in seas to the southwest of Portugal. The Journal of the Acoustical Society of America. 2020;147(4):2235 - 2249. Available at: http://asa.scitation.org/doi/10.1121/10.0001066.

Fripp D, Owen C, Quintana-Rizzo E, u. a. Bottlenose dolphin (Tursiops truncatus) calves appear to model their signature whistles on the signature whistles of community members.  2005. Available at: http://link.springer.com/10.1007/s10071-004-0225-z.