  In a recent Letter the phase diagram of Co/Cu/Ni/Cu(100) and Co/Fe/Ni/Cu(100)
trilayers was determined experimentally as well as theoretically. Whereas we do
not object the presented results, we remark that published work was not
commented on. Especially, much more information can be extracted out of the
measurements by a quantitative comparison with an appropriate model, allowing
for a determination of important parameters such as exchange coupling
constants.

Materials Science;Strongly Correlated Electrons