Filtration in Porous Media and Industrial Application: Lectures given at the 4th Session of the Centro Internazionale Matematico Estivo (C.I.M.E.) held in Cetraro, Italy August 24–29, 1998
“ Ego says, "Once everything falls into place, I'll feel peace." Spirit says "Find your peace, and then everything will fall into place." ” ― Marianne Williamson