Differentiation of Cefaclor and its delta‐3 isomer by electrospray mass spectrometry, infrared multiple photon dissociation spectroscopy and theoretical calculations. (January 2015) - Qian, Jian‐Qin; Correra, Thiago C.; Li, Jin; Maître, Philippe; Song, Dan‐Qing; Hu, Chang‐Qin