Guerstein et al., 2008
From dinoflaj3
Guerstein, G.R., Guler, M.V., Williams, G.L., Fensome, R.A. and Chiesa, J.O., 2008: Middle Palaeogene dinoflagellate cysts from Tierra del Fuego, Argentina: biostratigraphy and palaeoenvironments. Journal of Micropalaeontology, v.27, p.75-94, pl.1-5.