1. Ullmann. Encyclopedia of industrial chemistry (5. Auflage) “chromium and chromium alloys”, vol. A7. Weinheim: VCH; 1986. p. 43.
2. Gmelin. Handbook of inorganic and organometalic chemistry “chromium”, vol. 52. Berlin: Springer; 1963.
3. Greenwood N. Chemie der Elemente. Weinheim: Verlagsgesellschaft VCH; 1988. p. 440–53.
4. Holleman AF, Wiberg E. Lehrbuch der anorganischen Chemie, vol. 101. deGruyter: Auglage; 1995.
5. Khilla MA, Hanafi ZM, Mohamed AK. Physico-chemical properties of chromium trioxide and its suboxides. Thermochim Acta. 1982;59(2):139–47.