Keyword "SPONGOLITES" in:

Silicification of Korycany Member in Police Basin (Czech Republic)
Čáp,P., volume 40, 2007 (GRR for 2006), pages 15–20
pdf (1.11 MB)

Microscopic study of the silicified rocks and spongolites of the Bohemian Cretaceous Basin
Čáp,P., volume 39, 2006 (GRR for 2005), pages 107–108
pdf (0.12 MB)