Kirchner, M. & van Konijnenburg-van Cittert, J.H.A. 1994. Schmeissneria microstachys (Presl, 1833) Kirchner et Van Konijnenburg-Van Cittert, comb. nov. and Karkenia hauptmannii Kirchner et Van Konijnenburg-Van Cittert, sp. nov., plants with ginkgoalean affinities from the Liassic of Germany. Review of Palaeobotany & Palynology, 83: 199-215.