C. Álvarez-Cáliz, I. M. Santos-Dueñas, A. M. Cañete-Rodríguez, T. García-Martínez, J. C. Mauricio, and I. García-García, “Free amino acids, urea and ammonium ion contents for submerged wine vinegar production: influence of loading rate and air-flow rate”, Acetic Acid Bacteria, vol. 1, no. 1, p. e1, Apr. 2012.