Antimony: Data tables and historic information.
ChemGlobe: Antimony: Electronic, thermal, and steric data along with an isotope table.
ChemicalElements.com: Antimony: Basic information, atomic structure, and table of isotopes.
EnvironmentalChemistry.com: Antimony: Atomic structure, properties, and table of nuclides.
It's Elemental: Antimony: Basic physical and historical information.
LANL: Antimony: History, sources, properties, and uses.
Lenntech: Antimony: Physical data, chemical properties, health and environmental effects.
Radiochemistry of Antimony: Full text of the monograph by William J. Maeck (Phillips Petroleum Company, Atomic Energy Division, Idaho Falls, Idaho). [PDF]
USGS Minerals Information: Antimony: Overview and a number of publications in PDF format.
Visual Elements: Antimony: Image, source, uses, general and physical information, and key isotopes.
WebElements: Antimony: Extensive information on history, uses, occurrence, compounds, and properties.
Wikipedia: Antimony: Details the properties of the element, including its history, applications, and characteristics.