J. T. Karsulovic C., M. I. Dinator, J. Morales P., V. Gaete M., and A. Barrios R., “Determination of cylindrical defective core diameter in pruned Pinus radiata (D. Don) logs using gamma radiation attenuation”, BOSQUE, vol. 26, no. 1, pp. 109–122, Apr. 2005.