Spectroscopic infrared near-field microscopy and x-ray reflectivity studies of order and clustering in lipid membranes. - Generosi, J.; Margaritondo, G.; Sanghera, J. S.; Aggarwal, I. D.; Tolk, N. H.; Piston, D. W.; Castellano, A. Congiu; Cricenti, A. (Applied Physics Letters, 2006)