Antisense DNA oligonucleotides. II: The use of matrix-assisted laser desorption/ionization mass spectrometry for the sequence verification of methylphosphonate oligodeoxyribonucleotides. - Keough T; Baker TR; Dobson RL; Lacey MP; Riley TA; Hasselfield JA; Hesselberth PE (Rapid communications in mass spectrometry : RCM, 1993)