AOL.com http://search.aol.com/cat.adp?id=6...

AltaVista http://www.altavista.com/...

AlltheWeb http://www.alltheweb.com/...

Ask Jeeves http://www.ask.com/...

Compuserve http://webcenters.netscape.compuserve.com/menu/default.jsp...

Dogpile http://www.dogpile.com/...

Google http://www.google.com/ig?hl=en...

Google Deutschland http://www.google.de/...

Google Japan http://www.google.co.jp/...

Google学术搜索 http://scholar.google.com/...