Cholinesterase-inhibiting new steroidal alkaloids from Sarcococca hookeriana of Nepalese origin, Choudhary, M, I.; Devkota, K, P.; Nawaz, S, A.; Farzana Shaheen,; Atta-ur-Rahman, , Helvetica Chimica Acta, Volume 87, Number 5, p.1099-1108, (2004) Abstract