^Kobayashi, Shuji; Langguth, Alfredo (1999). "A new species of titi monkey, Callicebus Thomas, from north-eastern Brazil (Primates, Cebidae)". Revta bras. Zool: 531–551.
^Kobayashi, Shuji; Langguth, Alfredo (1999). "A new species of titi monkey, Callicebus Thomas, from north-eastern Brazil (Primates, Cebidae)". Revta bras. Zool: 531–551.