H. Robert Göppert, ?Die fossile Flora der Permischen Formation?, Palaeontographica, vol. 12, no. Lieferung 5-6, pp. p. 225-316, pls XLI-LXIV, 1865.

H. Robert Göppert, ?Die fossile Flora der Permischen Formation?, Palaeontographica, vol. 12, no. Lieferung 1-4, pp. p. 1-224, pls I-XL, 1864.