EuroPub
CaRLO
PKP (Public Knowledge Project)
CAS (Chemical Abstracts Services)
San José State University (California, United States) library
Google Scholar, USA
Electronic Journals Index, USA
WorldCat, USA
Index Copernicus, Poland
Genamics Journal Seek, USA
JournalTOCs, USA
Research Bib, Japan
BASE (Bielefeld Academic Search Engine), Germany
Scientific Index Services (SIS)
SUDOC
WorldWideScience
CiteFactor
ROAD - Directory of Open Access Scholary Resources
Zeitschriftendatenbank (ZDB)
CrossRef USA
Academia
iThenticate
publons
ScienceOpen
Cobiss
TIB
SLUB
osmikon
Dimensions
Teeal
CIVILICA
Academic Journals Database
FreeFullPDF
Journals Directory
Advanced Sciences Index
ISI
