• Modeling calcium dissolution from oil shale ash. Part 2, Continuous washing of the ash layerVelts, Olga; Hautaniemi, Marjaana; Kallas, Juha; Kuosa, Markku; Kuusik, Rein, keemikFuel processing technology2010 / 5, p. 491-495 : ill https://www.sciencedirect.com/science/article/pii/S0378382009003579