*{{cite|author1=Atkins, Peter W. and |author2=Julio de Paula ''|title=Physical Chemistry'', |edition=4th Edition, |publisher=Wiley-VCH, |location=Weinheim|year=2006, ISBN|isbn= 978-3-527-31546-8}}.
*{{cite|author1=Brock, William H. [|url=http://books.google.com/books?id=AJ-c8py7t6gC&pg=PA459 ''|title=Viewegs Geschichte der Chemie'']. |publisher=Vieweg, |location=Braunschweig|year=1997, ISBN |isbn=3-540-67033-5}}.
*{{cite|author1=Wiberg, Egon, |author2=Wiberg, Nils and |author3=Holleman, Arnold Frederick [|url=http://books.google.com/books?id=Mtth5g59dEIC&pg=PA287|title=Inorganic chemistry], |publisher=Academic Press, |year=2001 ISBN |isbn=0-12-352651-5}}.