Terbium
Links
Visual Elements: Terbium
http://www.chemsoc.org/viselements/pages/terbium.html
Image, source, physical information, and key isotopes.
It's Elemental: Terbium
http://education.jlab.org/itselemental/ele065.html
Provides information on history and properties.
ChemicalElements.com: Terbium
http://www.chemicalelements.com/elements/tb.html
Basic information, atomic structure, and isotopes.
EnvironmentalChemistry.com: Terbium
http://environmentalchemistry.com/yogi/periodic/Tb.html
Atomic structure, chemical and physical properties, and table of nuclides.
WebElements: Terbium
http://www.webelements.com/webelements/elements/text/Tb/key.html
Extensive information on history, uses, occurrence, compounds, and properties.
Lenntech: Terbium
http://www.lenntech.com/Periodic-chart-elements/Tb-en.htm
Physical data, chemical properties, health and environmental effects.