Britannica Nobel Prize: Americium
   Overview and basic data.
   http://www.britannica.com/nobel/micro/19_69.html

ChemGlobe: Americium
   Electronic, thermal, and steric data along with an isotope table.
   http://partisans.spurious.biz/~pkremer/projects/chemglobe/ptoe/_/95.html

ChemicalElements.com: Americium
   Basic information, atomic structure, and isotopes.
   http://www.chemicalelements.com/elements/am.html

EnvironmentalChemistry.com: Americium
   Atomic structure, properties, and table of nuclides.
   http://environmentalchemistry.com/yogi/periodic/Am.html

It's Elemental: Americium
   Basic physical and historical information.
   http://education.jlab.org/itselemental/ele095.html

LANL: Americium
   Basic information and history.
   http://periodic.lanl.gov/elements/95.html

Lenntech: Americium
   Physical data, chemical properties, health and environmental effects.
   http://www.lenntech.com/Periodic-chart-elements/Am-en.htm

Visual Elements: Americium
   Image, general and physical information, and key isotopes.
   http://www.chemsoc.org/viselements/pages/americium.html