  We have investigated the ferrimagnetic domain structure in a
Gd$_{0.67}$Ca$_{0.33}$MnO$_{3}$ thin film using magnetic force microscopy. We
observe clear signs of phase separation, with magnetic islands embedded in a
non-magnetic matrix. We also directly visualize the reversal of magnetization
of ferrimagnetic domains as a function of temperature and attribute it to a
change in the balance of magnetization of anti-aligned Mn and Gd sublattices.
