M. H. Razali, U. M. Osman, M. Z. H. Mohd Rozaini, and M. Yusoff, “Thermal Stability on Morphology and Crystal Structures of Hydrothermally Synthesized Titanate Nanotubes and Their Photocatalytic Activity”, ajc, vol. 29, no. 10, pp. 2207–2210, Aug. 2017.