ChemGlobe: Osmium
- Electronic, thermal, and steric data along with an isotope table.
- http://partisans.spurious.biz/~pkremer/projects/chemglobe/ptoe/_/76.html

LANL: Osmium
- Sources, properties, handling, and uses.
- http://periodic.lanl.gov/elements/76.html

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

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

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

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

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

It's Elemental: Osmium
- Basic physical and historical information.
- http://education.jlab.org/itselemental/ele076.html

Radiochemistry of Osmium
- Full text of the monograph by G. W. Leddicotte (Oak Ridge National Laboratory, Oak Ridge, Tennessee). [PDF]
- http://lib-www.lanl.gov/cgi-bin/getfile?rc000023.pdf