- Ricardo H Nochetto: Department of Mathematics and Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742, USA rhn@math.umd.edu.
- Enrique Otárola: Department of Mathematics, University of Maryland, College Park, MD 20742, USA Department of Mathematical Sciences, George Mason University, Fairfax, VA 22030, USA.
- Abner J Salgado: Department of Mathematics, University of Tennessee, Knoxville, TN 37996, USA.