1. K. Kumar, International scenario in capacitor industry, Electronics Information and Planning, July–August, 2000, 272 pp.
2. U.S. Patent No. 4940490.
3. L.D. Cunningham, Columbium (niobium and tantalum), Mineral Commodity Summaries, 1998, UI.
4. Tantalum–Niobium International Study Center (TIC) Bull. No. 104, Dec. 1998.
5. Tantalum capacitors: global trends in 2000;Passive Compon. Ind.,2000