  The reaction p d -> d phi p_{sp} is studied within the Bethe-Salpeter
formalism. Under special kinematical conditions (slow backward spectator proton
p_{sp} and fast forward deuteron) relevant for forthcoming experiments at COSY,
the cross section and a set of polarization observables factorize in the
contribution of the pure subprocess p n -> d phi and a contribution stemming
from deuteron quantities and kinematical factors. This provides a theoretical
basis for studying threshold-near processes at quasi-free neutrons.
