Sheldon, E., E. S. Rasmussen, K. Dybkjær, T. Eidvin, F. Riis, and R. Weibel. “Miocene Oil-Bearing Diatom Ooze from the North Sea”. GEUS Bulletin, vol. 41, Aug. 2018, pp. 29-32, doi:10.34194/geusb.v41.4335.