Helicosphaera reticulata Bramlette & Wilcoxon, 1967
Aubry, M. -P. & Bord, D. 2009. Reshuffling the cards in the photic zone at the Eocene/Oligocene boundary. In: Koeberl, C., Montanari, A. (eds), The Late Eocene Earth-Hothouse, Icehouse, and Impacts. Geological Society of America, Special Papers 452: 279-301.
Bramlette, M. N., Wilcoxon, J. A., 1967. Middle Tertiary calcareous nannoplankton of the Cipero section, Trinidad, W.I. Tulane Studies in Geology and Paleontology 5, 93-131.
Helicosphaera reticulata
Bramlette & Wilcoxon, 1967
Early Oligocene