First Specimens of the Cornutan Stylophoran Phyllocystis (Echinodermata) in the Ordovician (Volkhov Regional Stage, Dapingian and Darriwilian) of Baltica and Special Aspects of Stylophoran Axial Symmetry. Paleontological Journal, 58(2), Apr 2024: 181-195. 182 [Zoological Record Volume 160]