Cäsar, and Young; Young, RJ (2008). "A case of adoption in a wild group of black-fronted titi monkeys (Callicebus nigrifrons)". Primates. 49 (2): 146–148. doi:10.1007/s10329-007-0066-x. PMID17938856.
Vermeer, J.; Tello-Alvarado, J. C. (2015). "The Distribution and Taxonomy of Titi Monkeys (Callicebus) in Central and Southern Peru, with the Description of a New Species". Primate Conservation. 29: 9–29. doi:10.1896/052.029.0102.
Dalponte, Julio César; Silva, Felipe Ennes; Silva Júnior, José de Sousa e. (2014). "New species of titi monkey, genus Callicebus Thomas, 1903 (Primates, Pitheciidae), from Southern Amazonia, Brazil". Papéis Avulsos de Zoologia. 54. doi:10.1590/0031-1049.2014.54.32.
Cäsar, and Young; Young, RJ (2008). "A case of adoption in a wild group of black-fronted titi monkeys (Callicebus nigrifrons)". Primates. 49 (2): 146–148. doi:10.1007/s10329-007-0066-x. PMID17938856.