http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Spoehr, Herman Augustus: The Nature of progress in science. 1935
Spoehr, Herman Augustus: The Nature of progress in science. 1935 -- in: Angell, James Rowland: Popular and unpopular science. [36. 20975 -- BZD