A l m e i d a A. M., F i g e i r e d o R. A. 2003. Ants visit nectaries of Epidendrum denticulatum (Orchidaceae) in a Brazilian rainforest: effects on herbivory and pollination. Brazilian J. 63: 551-558.
B e l l A. K., R o b e r t s D. L., H a w k i n s J. A., R u d a l l P. J., Box M. S., B a t e m a n R. 2009. Comparative micromorphology of nectariferous and nectarless labellar spurs in selected clades of subtribe Orchidinae (Orchidaceae). Botanical Journal of the Linnean Society, 160: 369-387.
B r a g a P. 1977. Aspectos biologicos das Orchidaceae da Amazônica Central. Acta Amazonica Manaus, 7: 1-89. Da r wi n C. 1862. On the various contrivances by which British and foreign orchids are fertilized by insects and on