16.
Suárez-Ruiz i in. 2017 – Suárez-Ruiz, I., Valentim, B., Borrego, A.G., Bouzinos, A., Flores, D., Kalaitzidis, S., Malinconico, M.L. Marques, M. Misz-Kennan, M. Predeanu, G. Montes, J.r. Rodrigues, S. Siavalas, G. i Wagner, N. 2017. Development of a petrographic classification of fly-ash components from coal combustion and co-combustion. (An ICCP Classification System, Fly-Ash Working Group – Commission III). International Journal of Coal Geology 183, s. 188–203.