Holmium
Links
Visual Elements: Holmium
http://www.chemsoc.org/viselements/pages/holmium.html
Image, source, uses, key isotopes, and ionisation energies.
ChemicalElements.com: Holmium
http://www.chemicalelements.com/elements/ho.html
Basic information, atomic structure, and isotopes table.
It's Elemental: Holmium
http://education.jlab.org/itselemental/ele067.html
Basic physical and historical information.
EnvironmentalChemistry.com: Holmium
http://environmentalchemistry.com/yogi/periodic/Ho.html
Atomic structure, chemical and physical properties, and table of nuclides.
WebElements: Holmium
http://www.webelements.com/webelements/elements/text/Ho/key.html
Extensive information on history, uses, occurrence, compounds, and properties.
Lenntech: Holmium
http://www.lenntech.com/Periodic-chart-elements/Ho-en.htm
Physical data, chemical properties, health and environmental effects.