Project Gutenberg 2014-11-22 Public domain in the USA. 93 Bohr, Niels 1885 1962 Bohr, N. (Niels) Bohr, Niels Henrik David On the Quantum Theory of Line-Spectra, Part 1 and 2 en Quantum theory Spectrum analysis QC Text Physics 766804 2014-11-22T08:22:04 application/pdf 9419 2025-09-19T05:18:03.417338 application/rdf+xml 424334 2021-06-11T17:21:37 application/prs.tex 16182 2025-09-19T05:18:03.355312 image/jpeg 3667 2025-09-19T05:18:03.109323 image/jpeg 748668 2014-11-22T08:22:04 application/octet-stream application/zip 112368 2021-06-11T17:21:37 application/octet-stream application/zip Archives containing the RDF files for *all* our books can be downloaded at https://book.klll.cc/wiki/Gutenberg:Feeds#The_Complete_Project_Gutenberg_Catalog en.wikipedia