SDSS DR7 superclusters - Principal component analysis M. Einasto, L. J. Liivamägi, E. Saar, J. Einasto, E. Tempel, E. Tago and V. J. Martínez A&A, 535 (2011) A36 Published online: 28 October 2011 DOI: 10.1051/0004-6361/201117529