[1] Ahmed, M. M., “Effect of comminution on particle shape and surface roughness and their relation to flotation process”, International Journal of Mineral Processing, vol. 94, pp. 180-191, 2001.
                                                                                                                [2] Ahmed, P. T. and Nguyen A.V., “Validation of the generalised Sutherland equation for bubble–particle
                                                                                                                encounter efficiency in flotation: Effect of particle density”, Minerals Engineering, vol. 22, pp. 176-181,
                                                                                                                2009.
                                                                                                                [3] Małysa, E., “The effect of hard coal density on its flotation performance”, Acta Montanistica Slovaca,
                                                                                                                vol. 10, 2005.
                                                                                                                [4] Yoon, R. H., “The role of hydrodynamic and surface forces in bubble–particle interaction”, International Journal of Mineral Processing, vol. 58, pp. 129-143, 2000.
                                                                                                                [5] Reay, D. and Ratcliff, G., “Removal of fine particles from water by dispersed air flotation: effects of bubble
                                                                                                                size and particle size on collection efficiency”, The Canadian Journal of Chemical Engineering, vol. 51, pp. 178-185, 1973.
                                                                                                                [6] Weber, M. and Paddock, D., “Interceptional and gravitational collision efficiencies for single collectors
                                                                                                                at intermediate Reynolds numbers”, Journal of Colloidand Interface Science, vol. 94, pp. 328-335, 1983.
                                                                                                                [7] Schimmoler, B., Lutrell, G., and Yoon, R., “A combined hydrodynamic-surface force model for bubble-particle collection”, in Proc. XVIII Intern.Miner. Process. Congress, Sydney, pp. 751-756, 1993.
                                                                                                                [8] Bustamante, H. and Warren, L., “Relation between the relative density of composite coaly grains and their
                                                                                                                flotation recovery”, International Journal of Mineral Processing, vol. 10, pp. 95-111, 1983.
                                                                                                                [9] Yoon, R. and Luttrell, G., “The effect of bubble size on fine particle flotation”, Mineral Procesing and
                                                                                                                Extractive Metallurgy Review, vol. 5, pp. 101-122,1989.
                                                                                                                [10] Małysa, E., “Wpływ uziarnienia na wyniki floatacji węgla kamiennego”, Gospodarka Surowcami
                                                                                                                Mineralnymi, vol. 16, pp. 29-41, 2000.
                                                                                                                [11] Laskowski, J., “Wzbogacanie flotacyjne”, Poradnik Górnika T. 5. Wyd. Śląsk. Katowice (in Polish), 1976.
                                                                                                                [12] Jowett, A., “Formation and disruption of particlebubble aggregates in flotation”, Fine Particles Processing, vol. 1, pp. 720-754, 1980.
                                                                                                                [13] Maoming, F., Daniel, T., HONAKER, R. and Zhenfu, L., “Nanobubble generation and its applications
                                                                                                                in froth flotation (part IV): mechanical cells and specially designed column flotation of coal”, Mining
                                                                                                                Science and Technology, China, vol. 20, pp. 641-671,2010.
                                                                                                                [14] Shen, H., Forssberg, E., and Pugh, R., “Selective flotation separation of plastics by chemical conditioning with methyl cellulose”, Resources,conservation and recycling, vol. 35, pp. 229-241,2002.
                                                                                                                [15] Van der Westhuizen, A. and Deglon, D., “Solids suspension in a pilot-scale mechanical flotation cell: A critical impeller speed correlation”, Minerals Engineering, vol. 21, pp. 621-629, 2008.