Wille, Alvaro. 1967. “A New Species of Stingless Bee <i>Trigona (Plebeia)</i> From Costa Rica, With Descriptions of Its General Behavior and Cluster-Type Nest”. Revista De Biología Tropical 15 (2):299–313. https://doi.org/10.15517/rev.biol.trop. v15i2.28471.