Weeks, Mary Elvira (1932). "The discovery of the elements. II. Elements known to the alchemists". Journal of Chemical Education9 (1): 11. doi:10.1021/ed009p11. Bibcode: 1932JChEd...9...11W.
Weeks, Mary Elvira (1932). "The discovery of the elements. II. Elements known to the alchemists". Journal of Chemical Education9 (1): 11. doi:10.1021/ed009p11. Bibcode: 1932JChEd...9...11W.