Boron: Data tables and historic information.
Boron: Comprehensive historical data about the element and its compounds.
BoronWeb: Boron chemistry and links to boron chemists around the world.
ChemGlobe: Boron: Electronic, thermal, and steric data, along with general information.
ChemicalElements.com: Boron: Basic information, atomic structure, and table of isotopes.
EnvironmentalChemistry.com: Boron: Atomic structure, chemical and physical properties, and table of nuclides.
It's Elemental: Boron: Basic physical and historical information.
LANL: Boron: History, sources, uses, and properties.
Lenntech: Boron: Physical data, chemical properties, health and environmental effects.
USGS Minerals Information: Boron: Statistics and information on the worldwide supply, demand, and flow of the element (PDF format).
Visual Elements: Boron: Image, animation, source, uses, physical information, and covalent bonds.
WebElements: Boron: Extensive information on history, uses, occurrence, compounds, and properties of the element.
Wikipedia: Boron: Properties of the element, including its history, applications, and characteristics.