I. L. Fabricius, L. Dahlerup Fazladic, A. Steinholm, and U. Korsbech, “The use of spectral natural gamma-ray analysis in reservoir evaluation of siliciclastic sediments: a case study from the Middle Jurassic of the Harald Field, Danish Central Graben”, GEUS Bulletin, vol. 1, pp. 349–366, Oct. 2003, doi: 10.34194/geusb.v1.4677.