It's Elemental: Phosphorus - Basic physical and historical information. ChemicalElements.com: Phosphorus - Basic information, atomic structure, and table of isotopes. EnvironmentalChemistry.com: Phosphorus - Atomic structure, chemical and physical properties, and table of nuclides. Lenntech: Phosphorus - Physical data, chemical properties, health and environmental effects. Wikipedia: Phosphorus - Properties of the element, including its history, applications, and characteristics. Radiochemistry of Phosphorus - Full text of the monograph by William T. Mullins and G. W. Leddicote (Oak Ridge National Laboratory, Oak Ridge, Tennessee). WebElements: Phosphorus - Extensive information on history, uses, occurrence, compounds, and properties of the element.