Lund and Ecke, 1988
From dinoflaj2
Lund, J.J. and Ecke, H.-H., 1988: Dinoflagellate cyst stratigraphy applied to the Middle to Late Jurassic of the Regensburg-Passau area, Bavaria. Bulletin des Centres de recherches exploration-production Elf-Aquitaine, v.12, no.1, p.345-359, pl.1-3.