Rind, F.M.A., Laghari, M.G.H., Memon, A.H., Khuhawar, M.Y., AND Maheshwari, M.L.. "Spectrophotometric determination of ceftriaxone using 4-dimethylaminobenzaldehyde" Pakistan Journal of Analytical & Environmental Chemistry [Online], Volume 9 Number 1 (2 June 2008)