http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Fundamental Principles of General Relativity Theories
Local and Global Aspects of Gravitation and Cosmology
by Hans-Jürgen Treder, Horst-Heino Borzeszkowski, Alwyn Merwe, Wolfgang Yourgrau.