Promethium
Links
Visual Elements: Promethium
http://www.chemsoc.org/viselements/pages/promethium.html
Image, animation, source, uses, and ionisation energies.
Promethium
http://www.scescape.net/~woods/elements/promethium.html
Data table and historic information.
It's Elemental: Promethium
http://education.jlab.org/itselemental/ele061.html
Basic physical and historical information.
ChemicalElements.com: Promethium
http://www.chemicalelements.com/elements/pm.html
Basic information, atomic structure, and isotopes.
EnvironmentalChemistry.com: Promethium
http://environmentalchemistry.com/yogi/periodic/Pm.html
Atomic structure, chemical and physical properties, and table of nuclides.
WebElements: Promethium
http://www.webelements.com/webelements/elements/text/Pm/key.html
Extensive information on history, uses, occurrence, compounds, and properties.
Lenntech: Promethium
http://www.lenntech.com/Periodic-chart-elements/Pm-en.htm
Physical data, chemical properties, health and environmental effects.