Faghihi, Kh., et al. “Synthesis and Characterization of New Optically Active Copolyamides Based on N-Phthaloyl-L-Glutamic Acid, Terephthalic, Fumaric and Adipic Acids”. Asian Journal of Chemistry, vol. 24, no. 5, Jan. 2012, pp. 2025-7, https://asianpubs.org/index.php/ajchem/article/view/8948.