1. Depolarization Effects in Polycrystalline Sintered BaTiO3;Kniekamp;Naturwissenschaften,1954
2. 3 R. J. Lockhart et al., “Ultra-Fine Particle Size Ferroelectrics,” Army Electronics Research and Development Laboratory, Fort Monmouth, N. J., Final Report; Contract No. DA 36-039 sc-89203; July 1964.
3. Dielectric and Structural Studies in the Systems Ba(Ti, Nb)O3 and Ba(Ti, Ta)O3;Subbarao;J. Am. Ceram. Soc.,1959