Nazir, M., W. Ahmad, and W. Kreiser. “?ISOLATIONANDNMR-ASSIGNMENTS OF 19aH-LuPEOL FROME. HELIOSCOPIA LINN (N.O. EUPHORBIACEAE)”. Biological Sciences - PJSIR, vol. 41, no. 1, Feb. 1998, pp. 6-10, http://v2.pjsir.org/index.php/biological-sciences/article/view/2219.