Luo Mei, et al. “Study on Synthesis of N–Zn, and N–Cu Complexes Involving 2-Amino Pyridine and Ethylenediamine Ligands With an Application to the Henry Reaction”. Progress in Chemical Science Research Vol. 7, Mar. 2023, pp. 62-70, doi:10.9734/bpi/pcsr/v7/3260C.