1 SUPPLEMENTARY MATERIALS Selecting an Appropriate Multivariate Source Apportionment Model Result Ronald C. Henry a, * and Erik R. Christensen b a Department of Civil and Environmental Engineering, Environmental Engineering Program, University of Southern California, 3620 South Vermont Ave., Los Angeles, CA 90089-2531, USA b Department of Civil Engineering and Mechanics, University of Wisconsin- Milwaukee, 3200 N Cramer St. Milwaukee, Wisconsin 53211 No. of pages: 25 (including this cover sheet) No. of tables: 32 No. of figures: 4 _____________________ *Corresponding author phone (213) 740-0596