  We analyse the proton-induced Drell-Yan production in both the flavor
asymmetry and isospin breaking explanations for the violation of the Gottfried
sum rule. Consequences from three different forms of corrections to the flavor
and isospin symmetric parton distributions are examined. It is found that the
calculated results are sensitive to the choices of parameters and parton
distributions, and to the ways the corrections are introduced. All three forms
of corrections could be consistent with the recent Fermilab Experiment E772
data for the ratio of cross section $R=\sigma_{W}/\sigma_{IS}$ and for the
shape of the differential cross section $m^{3}d^{2}\sigma/dx_{F}dm$ for
$^{2}$H.
