Lind, A., du Fresne von Hohenesche, C., Smått, J. H., Lindén, M., & Unger, K. K. (2003). Spherical silica agglomerates possessing hierarchical porosity prepared by spray drying of MCM-41 and MCM-48 nanospheres. Microporous and Mesoporous Materials, 66(2-3), 219-227. doi:10.1016/j.micromeso.2003.09.011.