A. Kamil Rashid, R. Binti Yahya, and P. Sook Wai, “Synthesis, Characterization, Effect of Triaryl Ring Substituents Groups on Thermal and Spectral Properties of New Soluble Triphenylamine-Based Aromatic Polyamides”, ajc, vol. 26, no. 1, pp. 85–92, Dec. 2013.