Juris Hartmanis, Neil Immerman, Vivian Sewelson. Sparse Sets in NP-P: EXPTIME versus NEXPTIME. Information and Control, volume 65, issue 2/3, pp.158–181. 1985. At ACM Digital LibraryArchive.is的存檔,存档日期2012-07-12
archive.today
Juris Hartmanis, Neil Immerman, Vivian Sewelson. Sparse Sets in NP-P: EXPTIME versus NEXPTIME. Information and Control, volume 65, issue 2/3, pp.158–181. 1985. At ACM Digital LibraryArchive.is的存檔,存档日期2012-07-12
psu.edu
citeseer.ist.psu.edu
Jin-Yi Cai and D. Sivakumar. Sparse hard sets for P: resolution of a conjecture of Hartmanis. Journal of Computer and System Sciences, volume 58, issue 2, pp.280–296. 1999. ISSN:0022-0000. At Citeseer (页面存档备份,存于互联网档案馆)
web.archive.org
Jin-Yi Cai and D. Sivakumar. Sparse hard sets for P: resolution of a conjecture of Hartmanis. Journal of Computer and System Sciences, volume 58, issue 2, pp.280–296. 1999. ISSN:0022-0000. At Citeseer (页面存档备份,存于互联网档案馆)