We show that a double-Baer group implies the existence of a
double-retraction in a translation plane with kernel containing a field
. If the associated
spread is in
then
a lifted spread in
admits a double-Baer group. The double-retraction group produces a maximal partial mixed
partition of
of lines and
.
This result is generalized and new examples of translation planes admitting
double-Baer groups are given.