• Sulphation of Estonian and Israeli oil shale ashes under atmospheric and pressurized combustion conditionsKülaots, Indrek; Ots, Arvo; Yrjas, Patrik; Hupa, Mikko; Backman, P.Oil shale1997 / 3, p. 265-283: ill https://artiklid.elnet.ee/record=b2315277*est