J. P. Gómez Montoya, K. P. Cacua Madero, L. Iral Galeano, and A. A. Amell Arrieta, “Effect of biogas enriched with hydrogen on the operation and performance ofa diesel-biogas dual engine”, CT&F Cienc. Tecnol. Futuro, vol. 5, no. 2, pp. 61–72, Jun. 2013.