Aduri Pavan Alan L. Selman Bi-Immunity Separates Strong NP-Completeness Notions Electronic Colloquium on Computational Complexity (ECCC) 2002 005 db/journals/eccc/eccc9.html#ECCC-TR02-005 http://eccc.hpi-web.de/eccc-reports/2002/TR02-005/index.html