WorldWideScience research gateway

    https://worldwidescience.org/wws/desktop/en/search.html

    Aggregates 200 international research institutions and permits a centralized search on their research articles and databases. If you must start somewhere, start here!

    An institution by institution filter is provided, so as an automatic translation. Again, a must.

    Tip: The link above is the advanced search. Go to the home page to get the simplified search.

    Free, No Download/Install required, No registration