L. W.  Chatrou, Rainer, H., and Maas, J. M., ?Annonaceae?, in Flowering Plants of the Neotropics, N.  Smith, Mori, S. A., Henderson, A., Stevenson, D. W., and Heald, S. V., Eds. Princeton: Princeton University Press, 2004, pp. 18-20.

L. W.  Chatrou, Rainer, H., and Maas, J. M., ?Annonaceae?, in Flowering Plants of the Neotropics, N.  Smith, Mori, S. A., Henderson, A., Stevenson, D. W., and Heald, S. V., Eds. Princeton: Princeton University Press, 2004, pp. 18-20.