Check-lists
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Links and literature
[1] Chlupáč I., Kordule V. (2002): Arthropods of Burgess Shale type from the Middle Cambrian of Bohemia (Czech Republic), Bulletin of the Czech Geological Survey, Vol. 77, No. 3, 167–182 [as Helmetia fastigata Chlupáč & Kordule, 2002]
Chlupáč I., Kordule V. (2002): Arthropods of Burgess Shale type from the Middle Cambrian of Bohemia (Czech Republic), Bulletin of the Czech Geological Survey, Vol. 77, No. 3, 167–182 [as Helmetia fastigata Chlupáč & Kordule, 2002]