Rhenium

ChemGlobe: Rhenium - Electronic, thermal, and steric data along with an isotope table.
http://partisans.spurious.biz/~pkremer/projects/chemglobe/ptoe/_/75.html

It's Elemental: Rhenium - Basic physical and historical information.
http://education.jlab.org/itselemental/ele075.html

LANL: Rhenium - History, sources, properties, and uses.
http://periodic.lanl.gov/elements/75.html

Radiochemistry of Rhenium - Full text of the monograph by G. W. Leddicotte (Oak Ridge National Laboratory, Oak Ridge, Tennessee). [PDF] <small>(March, 1961)</small>
http://library.lanl.gov/cgi-bin/getfile?rc000051.pdf

WebElements: Rhenium - Extensive information on history, uses, occurrence, compounds, and properties.
http://www.webelements.com/webelements/elements/text/Re/key.html

ChemicalElements.com: Rhenium - Basic information, atomic structure, and isotopes.
http://www.chemicalelements.com/elements/re.html

EnvironmentalChemistry.com: Rhenium - Atomic structure, chemical and physical properties, and table of nuclides.
http://environmentalchemistry.com/yogi/periodic/Re.html

Visual Elements: Rhenium - General and physical information, source, uses, key isotopes, and ionisation energies.
http://www.chemsoc.org/viselements/pages/rhenium.html

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

USGS Minerals Information: Rhenium - Statistics and information on the worldwide supply, demand, and flow of the element (PDF format).
http://minerals.usgs.gov/minerals/pubs/commodity/rhenium/

Wikipedia: Rhenium - Properties of the element, including its history, applications, and characteristics.
http://en.wikipedia.org/wiki/Rhenium