5Mersmann H J. Overview of the effects of β - adrenergic receptor ago nists on animal growth including mechanisms of action [ J ]. J Anim Sci, 1998,76 : 160 - 172.
6Van Ginkel L A,Stephany R W, van Rossum H J. Development and validation of a multiesidue method for β - agonists in biological samples and animal feed [ J]. Journal of AOAC International, 1992,75 (3) :554 -560.