Columbia subject headings:
Coal--Colombia--Antioquia (Department)
Geology, Stratigraphic--Tertiary.
Geology--Colombia--Antioquia (Department)
Harvard subject headings:
Coal--Colombia--Antioquia (Department)
Geology, Stratigraphic--Tertiary
Geology--Colombia--Antioquia (Department)
Princeton subject headings:
Coal--Colombia--Antioquia (Dept.).
Geology, Stratigraphic--Tertiary.
Geology--Colombia--Antioquia (Dept.).