Ruiz Méndez, M. V., Liotta, A., Marmesat, S. and Dobarganes, M. C. (2008) “Detection of the presence of used frying oil as raw material in biodiesel production”, Grasas y Aceites, 59(4), pp. 383–388. doi: 10.3989/gya.2008.v59.i4.534.