9Abdulla M, Behbehani A, Dashti H. Dietary intake and bioavailability of trace elements[J]. Biol Trace Element Research, 1989, 21 (3):173- 178.
10Ellen G, Egmond E, Van Loon, et al. Dietary intakes of some essential and non-essential trace elements, nitrate nitrite and N-nitrosoamines by Duch adults estimated via a 24 hour duplicate portion study[J]. Food Addit Contam, 1990, 7(2):207-221.
