Carmo, J. A. M., M. Reginato, S. V. Sobrado, L. M. Miguel, S. B. Janssens, S. Dessein, R. M. Salas, y A. O. Simoes. «There and back again: molecular phylogenetics of the Brazilian endemic Psyllocarpus (Rubiaceae: Spermacoceae) supports a circumscription of the genus based on its original concept». Bonplandia 32 (octubre 26, 2023): 5. Accedido marzo 27, 2026. https://revistas.unne.edu.ar/index.php/bon/article/view/6942.