Meier, Roland; Grueschow, Sabine; Leumann, Christian Helvetica Chimica Acta, 1999, vol. 82, # 11 p. 1813 - 1828 doi: 10.1002/(SICI)1522-2675(19991110)82:11<1813::AID-HLCA1813>3.0.CO;2-0