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2. Progress in the chemistry of organic natural products vol. 42;Asakawa,1982
3. Sesqui- and diterpenoids from the liverwort Porella densifolia Subp. appendzculata and Porella densifolia Var. fallax;Asakawa;Phytochemistry,1987
4. Crystallographic data for the structure reported in this paper have been deposited at the Cambridge Crystallographic Data Centre (deposition number CCDC 764104). Copies of the data can be obtained, free of charge, on application to the Director, CCDC, 12 Union Road, Cambridge CB2 1EZ, UK (fax: +44-(0) 1223-336033 or e-mail:deposit@ccdc.cam.ac.uk).
5. MaXus computer program for the solution and refinement of crystal structures;Mackay,1999