Carboniferous Biostratigraphy, Western San Saba County, Texas
Robbie Rice Gries, B.S. Thesis 
The University of Texas at Austin, May 1971. 

In the pocket of the thesis, which can be found in the PRC-122 library,  is an excellent map that in conjunction with the appendices may resolve some enigmatic location codes.  These locations consolidate date from the following - Gries 1970, Humble 1955-1957, Oden 1958, Rose 1959, Defandorf 1960, Kuich 1964, and Turner 1970.

Appendix A - Measured Sections: Names, Localities, Previous Workers 

Includes section abbreviations like AT, EH, EBH, RC, etc.  So if you see something like "EBH section" or "RC.9" these might be worth checking out. 

Appendix B - Key Localities - Location codes like C14-1, T8-2, LK-11, etc.

These are the specific locations correlated by Rice and correspond to tags from the papers and theses listed above.

The underlined ones in his text are now followed by "*".

These *'d location names should appear at the Index Map coordinates that follow the corresponding entry. E.g., expect B13-2 at P-15.