★ CrossRef

★ Hein Online Database, W.S.HEIN, USA

★ Ulrich’s Periodicals Directory

★ Excellent papers in ERIC

★ ProQuest/CSA Social Science Collection, Public Affairs Information Service (PAIS), USA

★ Summon Serials Solutions

★ PBN (Polish Scholarly Bibliography)

★ Google Scholar

★ Chinese Database of CEPS, American Federal Computer Library Center (OCLC), USA

★ Chinese Scientific Journals Database, VIP Corporation, Chongqing, P.R.C.

★ J-Gate

★ SCRIBD

★ Academic Key

★ Pubicon Science

★ CiteFactor

★ Electronic Journals Library

★ Scientific Indexing Services

★ Newjour

★ Scholarsteer

★ Sherpa/Romeo

★ Pubget

★ WZB (Berlin Social Science Center)

★ ResearchBible

★ S-Journal Index

★ Turkish Education Index

★ Scientific Indexing Service

★ BASE

★ Infobase Index

★ WorldCat

★ Journal Index.net

★ Free Libs