Wikipedia, Aug. 25, 2012 (Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Like zinc, it prefers oxidation state +2 in most of its compounds and like mercury it shows a low melting point compared to transition metals. Cadmium and its congeners are not always considered transition metals, in that they do not have partly filled d or f electron shells in the elemental or common oxidation states. Element category: transition metal. Alternatively considered a post-transition metal)

It's elemental website, Aug. 24, 2012 (Cadmium. Element classification: Metal)

WebElements website, Aug. 24, 2012 (Cadmium is a soft, bluish-white metal and is easily cut with a knife. It is similar in many respects to zinc. Classification: Metallic)

Chemical Elements.com, Aug. 24, 2012 (Cadmium. Classification: Transition Metal)

Periodic table of the elements, via About.com Chemistry website, Aug. 24, 2012: Cd (Cadmium. Element Classification: Transition Metal)

Cadmium element facts, via Chemicool website, Aug. 24, 2012 (Classification: Cadmium is a transition metal. Some chemists don't regard cadmium as a true transition metal, because it has a full shell of d electrons. The IUPAC definition of a transition metal is one whose atoms have an incomplete d sub-shell, or which can give rise to cations with an incomplete d sub-shell. By this definition, cadmium, whose ions have incomplete d electron shells, is a transition metal.)