Não informado. (1999). Bulletin of the Czech Geological Survey. Czech Geological Survey.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Bulletin of the Czech Geological Survey. Praha: Czech Geological Survey, 1999.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Bulletin of the Czech Geological Survey. Czech Geological Survey, 1999.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.