Osácar, M.C. Sancho, C. Muñoz, A. Bartolomé, M. Moreno, A. Delgado-Huertas, A. Cacho, I. Tracking the oxygen isotopic signature from the rainfall to the speleothems in Ortigosa de Cameros caves (La Rioja, Spain) Estud. Geol. 10.3989/egeol.41730.319 2014 2014