Hedström, Ingemar, and Göran Sahlén. “A Key to the Adult Costa Rican ‘helicopter’ Damselflies (Odonata: Pseudostigmatidae) With Notes on Their Phenology and Life Zone Preferences”. Revista de Biología Tropical 49, no. 3-4 (December 1, 2001): 1037–1056. Accessed November 24, 2024. https://revistas.ucr.ac.cr/index.php/rbt/article/view/18052.