Databases, Libraries and antiquarian book-sellers
Reference / Dictionaries
Encyclopedia Britannica Online Academic Edition
Linguee Translations in context
LEO Dictionary
Pons Online Dictionary with german orthography
Other Libraries
Astronomical libraries
Astrobibliothek MPI for Astrophysics, MPI for Extraterrestrial Physics
AEI MPI for Gravitational Physics (Albert Einstein Institute)
MPIK MPI for Nuclear Physics
MPS MPI for Solar System Research
ESO European Southern Observatory
STScI Space Telescope Science Institute
Libraries of general interest
BSB Bavarian State Library, Munich
dnb German National Library
KVK Virtual Catalogue of the Karlsruhe Institute of Technology (KIT)
LOC Library of Congress
TIB Technology Information Library, Hannover University Library
Sales & Antiquarian catalogues
abebooks.de (antiquarische, vergriffene und gebrauchte Bücher kaufen und verkaufen)
Price finders for online bookshops
FetchBook.Info (Neue und gebrauchte Bücher - den niedrigsten Preis finden)