1. COPPEAD Graduate Business School, Federal University of Rio de Janeiro, Rua Paschoal, Lemme, 355, Rio de Janeiro 21949-900, Brazil
2. Getulio Vargas Foundation, EBAPE—Brazilian School of Public and Business Administration, Rio de Janeiro 22250-900, Brazil
3. School of Management, University of Bradford, Bradford BD7 1DP, UK
4. Department of Mathematics, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan 81595-158, Iran