1 Barnard P (Ed).Biological diversity in Namibia: a country study.Windhoek: Namibian National Biodiversity Task Force,Directorate of Environmental Affairs,1998.332pp. 
2 Mishra PD,Wahidulla S,Souza LD,et al.Lipid constituents of marine sponge Suberites Carnosus.Ind J Chem,1996, 35B:806-809. 
3 Yang XL,Wang F,Shao HJ,et al.Study on the chemical constitutes of Hydnellum concrescens.Nat Prod Res Dev(天然产物研究与开发),2007,19:605-609. 
4 Kawagishi H,Katsumi R,Sazawa T,et al.Cytotoxic steroids from the mushroom Agaricus blazei.Phytochemistry, 1988,27:2777-2779. 
5 Yaoita Y,Amemiya K,Ohnuma H,et al.Sterol constituents from five edible mushrooms.Chem Pharm Bull,1998,46: 944-950. 
6 Ma WG,Li CX,Wang DZ,et al.Ergosterol peroxides from cryptoporus volvatus.Acta Bot Yunnan,1994,16(2): 196-200. 
7 Tsantrizopsa YS,Folkinsja PL,Britten JK,et al.Approaches towards the synthesis of a sulfur analog of ergosterol peroxide.Can J Chem,1992,70:158-164. 
8 Gong YH,Ding LS.13C-NMR analysis of natural products.Kunming:Yunnan Science and Technology Press,2006. 884. 9 Gao JM,Hu L,Dong ZJ,et al.New glycosphingolipid containing an unusual sphingoid base from the basidiomycete Polyporus ellisii.Lipids,2001,36:571-574.
10 Higuch R,Inagaki M,Togawa K. Isolation and structure of cerebrosides from the sea cucumber Pentacta australis. Liebigs Ann Chem,1994,7:653-655.