Localization of fatty acyl and double bond positions in phosphatidylcholines using a dual stage CID fragmentation coupled with ion mobility mass spectrometry - Castro-Perez, J; Roddy, T P; Nibbering, N MM; Shah, V; McLaren, D G; Previs, S; Attygalle, A B; Herath, K; Chen, Z; Wang, S P; Mitnaul, L; Hubbard, B K; Vreeken, R J; Johns, D G; Hankemeier, T (J Am Soc Mass Spectrom, 2011)