Thanks! As the book (from 1922) seems to be out of copyright, here's a link to the PDF copy I found on archive.org. https://archive.org/details/einsteinstheori

Thanks! As the book (from 1922) seems to be out of copyright, here's a link to the PDF copy I found on archive.org. https://archive.org/details/einsteinstheorie0000bird https://archive.org/details/einsteinstheorie0000bird