| Britannica Nobel Prizes: Californium: Overview and basic data. |
| Californium: Data tables and historic information. |
| ChemGlobe: Californium: Electronic and thermal data along with an isotope table. |
| ChemicalElements.com: Californium: Basic information, atomic structure, and isotopes table. |
| EnvironmentalChemistry.com: Californium: Atomic structure, chemical and physical properties, and table of nuclides. |
| It's Elemental: Californium: Basic physical and historical information. |
| LANL: Californium: Basic information and history. |
| Lenntech: Californium: Physical data, chemical properties, health and environmental effects. |
| Visual Elements: Californium: General and physical information, uses, and key isotopes. |
| WebElements: Californium: Extensive information on history, uses, compounds, and properties. |