Toward understanding environmental effects in SDSS clusters J. Einasto, E. Tago, M. Einasto, E. Saar, I. Suhhonenko, P. Heinämäki, G. Hütsi and D. L. Tucker A&A, 439 1 (2005) 45-58 Published online: 22 July 2005 DOI: 10.1051/0004-6361:20042347