Nirmala, R., J. Jeong, R. Navamathavan, and H. Y. Kim. “Synthesis and Electrical Properties of TiO2 Nanoparticles Embedded in Polyamide-6 Nanofibers Via Electrospinning”. Nano-Micro Letters, vol. 3, no. 1, May 2011, pp. 56-61, doi:10.1007/BF03353651.