De Coninck, 2001
From dinoflaj2
de Coninck, J., 2001: Organic-walled microfossils in the Oligocene Grimmertingen and Neerrepen sand members from the Grimmertingen type locality. Service géologique de Belgique, Professional Paper 2001/2, no.294, p.1-57, pl.1-13.
