Check-lists
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Links and literature
[1] Štorch P. (2015): Graptolites from the Rhuddanian–Aeronian boundary interval (Silurian), Prague Synform, Czech Republic, Bulletin of Geosciences 90(4), 841–891 [as Pernerograptus austerus (Törnquist, 1899)]
Štorch P. (2015): Graptolites from the Rhuddanian–Aeronian boundary interval (Silurian), Prague Synform, Czech Republic, Bulletin of Geosciences 90(4), 841–891 [as Pernerograptus austerus (Törnquist, 1899)]