Londoño, John Makario. 2009. «RADON AND CO2 EMISSIONS IN DIFFERENT GEOLOGICAL ENVIRONMENTS AS A TOOL FOR MONITORING VOLCANIC AND SEISMIC ACTIVITY IN CENTRAL PART OF COLOMBIA». Boletín De Geología 31 (2). https://revistas.uis.edu.co/index.php/revistaboletindegeologia/article/view/352.