Weeks, Mary Elvira (1932). "The discovery of the elements. XII. Other elements isolated with the aid of potassium and sodium: Beryllium, boron, silicon, and aluminum". Journal of Chemical Education. 9 (8): 1386. Bibcode:1932JChEd...9.1386W. doi:10.1021/ed009p1386.
Kresse, Robert; Baudis, Ulrich; Jäger, Paul; Riechers, H. Hermann; Wagner, Heinz; Winkler, Jocher; Wolf, Hans Uwe (2007). "Barium and Barium Compounds". Dalam Ullman, Franz. Ullmann's Encyclopedia of Industrial Chemistry. Wiley-VCH. doi:10.1002/14356007.a03_325.pub2.
Petzow, G. N.; Aldinger, F.; Jönsson, S.; Welge, P.; Van Kampen, V.; Mensing, T.; Brüning, T. (2005). "Beryllium and Beryllium Compounds". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a04_011.pub2. ISBN3527306730.
Amundsen, K.; Aune, T. K.; Bakke, P.; Eklund, H. R.; Haagensen, J. Ö.; Nicolas, C.; Rosenkilde, C.; Van Den Bremt, S.; Wallevik, O. (2003). "Magnesium". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a15_559. ISBN3527306730.
Weeks, Mary Elvira (1932). "The discovery of the elements. XII. Other elements isolated with the aid of potassium and sodium: Beryllium, boron, silicon, and aluminum". Journal of Chemical Education. 9 (8): 1386. Bibcode:1932JChEd...9.1386W. doi:10.1021/ed009p1386.
"Radium", Los Alamos National Laboratory, diakses tanggal 2009-08-05
lbl.gov
ie.lbl.gov
Richard B. Firestone (15 March 2010). "Isotopes of Calcium (Z=20)". Lawrence Berkeley National Laboratory. Diarsipkan dari versi asli tanggal 2012-05-06. Diakses tanggal 12 June 2012.
Richard B. Firestone (15 March 2010). "Isotopes of Barium (Z=56)". Lawrence Berkeley National Laboratory. Diarsipkan dari versi asli tanggal 2012-05-06. Diakses tanggal 12 June 2012.
nih.gov
ncbi.nlm.nih.gov
Murray, T. (1993). "Elemementary Scots: The Discovery of Strontium". Scottish Medical Journal. 38 (6): 188–189. PMID8146640.
Hagler D.J., Jr; Goda Y. (2001). "Properties of synchronous and asynchronous release during pulse train depression in cultured hippocampal neurons". J. Neurophysiol. 85 (6): 2324–34. PMID11387379.
Richard B. Firestone (15 March 2010). "Isotopes of Calcium (Z=20)". Lawrence Berkeley National Laboratory. Diarsipkan dari versi asli tanggal 2012-05-06. Diakses tanggal 12 June 2012.
Richard B. Firestone (15 March 2010). "Isotopes of Barium (Z=56)". Lawrence Berkeley National Laboratory. Diarsipkan dari versi asli tanggal 2012-05-06. Diakses tanggal 12 June 2012.