Petrographic study of the limestones of the Rosablanca Formation Region of the Mesa de los Santos Region Zamarreño De Julivert 5-34 PDF (Español (España))
The Superficial Radioactivity in the Field "La Cira" and its possible relationship with the oil G. Trapp, H. F. Victoria 35-39 PDF (Español (España))
New observations on the Quaternary stratigraphy and tectonics around Bucaramanga Manuel Julivert 41-59 PDF (Español (España))
