1. Acritarchs from the Šárka Formation (Llanvirnian);Vavrdová;Věstnik Ústředniho éstavu geologickeho,1977
2. Excystment mechanism of early Paleozoic acritarchs;Vavrdová;Časopis pro mineralogii a geologii,1976
3. Acritarchs from the type area of the Ordovician Caradoc Series, Shropshire, England;Turner;Palaeontographica,1984
4. Sweet W. C. & Bergström S. M. 1976. Conodont biostratigraphy of the middle and upper Ordovician of the United States midcontinent. In The Ordovician System: Proceedings of a Palaeontological Association Symposium, Birmingham, September 1974 (ed. Bassett M. G. ), pp. 121–51. Cardiff: University of Wales Press and National Museum of Wales.