A. B.  Nawale, Kanhe, N. S., Patil, K. R., Bhoraskar, S. V., Mathe, V. L., and Das, A. K., ?Magnetic properties of thermal plasma synthesized nanocrystalline nickel ferrite (NiFe2O4)?, Journal of Alloys and Compounds, vol. 509, no. 12, pp. 4404-4413, 2011.