| details |
Early Givetian |
|
|
Grahn,Y. et al. Middle and Upper Devonian Chitinozoan biostratigraphy of the Parana Basin in Brazil and Paraguay. |
2002 |
| details |
Early Givetian |
|
Paraguay |
Grahn,Y. et al. Middle and Upper Devonian Chitinozoan biostratigraphy of the Parana Basin in Brazil and Paraguay. |
2002 |
| details |
Early Givetian |
|
|
Grahn,Y. Devonian chitinozoan biozones of Western Gondwana. |
2005 |
| original |
Early Givetian |
|
Brazil(Mato Grosso) |
de Almeida-Burjack,M.I. et al. Chitinozoas from the genus Alpenachitina of the Middle Devonian of Brazil; Interpretation of the stratigraphy and the phylogenetic relationship. |
1989 |