Robuta

https://journals.ku.edu/kgsbulletin/article/view/22097/19943 View of Coal Resources of the Marmaton Group in Eastern Kansas coal resources view group eastern kansas https://journals.ku.edu/kgsbulletin/article/view/20403 Distribution of the Bandera Shale of the Marmaton Group, Middle Pennsylvanian of Southeastern... of the distribution bandera shale group