See also:

• Science: Chemistry: Elements: Lanthanides  (2)

• ChemGlobe: Thulium - Electronic, thermal, and steric data along with an isotope table.
• ChemicalElements.com: Thulium - Basic information, atomic structure, and isotopes.
• EnvironmentalChemistry.com: Thulium - Atomic structure, chemical and physical properties, and table of nuclides.
• It's Elemental: Thulium - Basic physical and historical information.
• LANL: Thulium - Basic information and history.
• Lenntech: Thulium - Physical data, chemical properties, health and environmental effects.
• Visual Elements: Thulium - Image, uses, physical information, and ionisation energies.
• WebElements: Thulium - Extensive information on history, uses, occurrence, compounds, and properties.
• Wikipedia: Thulium - Properties of the element, including its history, applications, and characteristics.

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