Journal / article rating

HSGswisscovery and some other databases allow you to restrict your search to peer-reviewed journals.

Some databases like Web of Science or Scopus always list refereed journals only.

Ulrich's International Periodicals Directory can be useful to identify peer-reviewed journals.

Web of Science 
Using this interdisciplinary database allows you, among other things, to find out how often an article has been cited. Click the CITED REFERENCES tab to use the cited reference search and enter the journal title in abbreviated form. You will get a list of articles from this journal, each with a number of 'hits'. 

Scopus
Interdisciplinary database that shows, among others, how often an article has been cited and how relevant it is compared to similar articles. Analytical tools allow you to visualize your results.

Journal Citation Reports (JCR)
Contains a journal ranking. Choose your field, click on „Submit“ and sort the list by "Impact Factor".

Biographical information about authors and scientists may be found for example here:

• Kürschners Deutscher Gelehrten-Kalender: bio-bibliographical Index of German scientists of the present age.
• International: Nexis Uni
• The citation index Web of Science allows you to find out what influence a certain author has had on the research of other scientists in the field.