Composition #1: RESCH, JF., ROSBERGER, DF., MEINWALD, J., APPLING, JW. BIOLOGICALLY-ACTIVE PYRROLIZIDINE ALKALOIDS FROM THE TRUE FORGET-ME-NOT, MYOSOTIS-SCORPIOIDES. JOURNAL OF NATURAL PRODUCTS, 1982, vol. 45, no. 3, p. 358–362. DOI: 10.1021/np50021a020.
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