Classification
GCAA - Regional geology - Germany
3
GCAC - Regional geology - noneuropean countries
2
GHH - Sedimentary petrography - general
2
GHHF - Sedimentary basins
2
GBA - General geology, historical geology
1
GBAA - Geology - textbooks
1
GBAH - Stratigraphy, history of earth
1
GBC - Paleoclimatology
1
GBHC - Ocean floor - sediments, morphology
1
GCAB - Regional geology - european countries
1
GMP - Geochemical exploration
1
GWAA - Raw material programs
1