S. Hemchand, R. R. C. Babu, and M. M. Annapurna, “A new validated stability-indicating gradient RP-HPLC method for the determination of pemetrexed disodium and its process related substances”, J. Drug Delivery Ther., vol. 9, no. 3-s, pp. 588–610, Jun. 2019, doi: 10.22270/jddt.v9i3-s.2918.