| details |
Eocene |
|
Japan(Hokkaido I.) |
Tokunaga,S. Fossil pollen and spore from the known coal seams in the Bibai area, Ishikari Coal Field, Hokkaido. |
1955 |
| details |
Early Tertiary |
|
Japan(Hokkaido I.) |
Tokunaga,S. Pollen analysis of the known coal seams in the Biba Bibai area, Sorachi District, Ishikari Coal Fields, Hokkaido. |
1955 |
| details |
Early Tertiary |
|
Japan(Hokkaido I.) |
Tokunaga,S. Pollen analysis of the known coal seams in the Biba Bibai area, Sorachi District, Ishikari Coal Fields, Hokkaido. |
1955 |
| details |
Namurian A |
|
Germany |
Horst,U. Phase-contrast photography, a new aid for microscopic coal research. |
1950 |