Konrad Märkel

Functional anatomy of the valves in the ambulacral system of sea urchins (Echinodermata, Echinoida)

Konrad Märkel, Ursula Röser, 2005, Zoomorphology.

Mechanical design in spines of diadematoid echinoids (Echinodermata, Echinoidea)

Werner Hansmann, Hans-Jürgen Niemann, Anke Burkhardt, 1983, Zoomorphology.