ChemGlobe: Manganese
- Electronic, thermal, and steric data along with an isotope table.
- http://partisans.spurious.biz/~pkremer/projects/chemglobe/ptoe/_/25.html

LANL: Manganese
- Sources, properties, uses, and handling.
- http://periodic.lanl.gov/elements/25.html

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

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

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

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

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

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

It's Elemental: Manganese
- Basic physical and historical information.
- http://education.jlab.org/itselemental/ele025.html

Radiochemistry of Manganese
- Full text of the monograph by R. P. Schuman (Dept. of Chemistry, Robert College, Bebek P.K.8, Istanbul, Turkey). [PDF]
- http://lib-www.lanl.gov/cgi-bin/getfile?rc000060.pdf