A.S. van der Molen and Th.E. Wong 2007. Towards an improved lithostratigraphic subdivision of the Chalk Group in the Netherlands North Sea area - A seismic stratigraphic approach. Netherlands Journal of Geosciences. 86, (Jul. 2007), 131 - 143. DOI:https://doi.org/10.1017/S0016774600023131.