  We have carried out elastic neutron scattering measurements on
La$_{1.875}$Ba$_{0.075}$Sr$_{0.05}$CuO$_4$ single crystal ($T_c\approx$10K).
Incommensurate elastic magnetic peaks were observed in the low-tamperature
tetragonal phase with the propergation vector parallel/perpendicular to
in-plane Cu-O bond direction. The magnetic peak intensity normalized by the
sample volume is approximately six times larger than that of the orthorhombic
La$_{1.88}$Sr$_{0.12}$CuO$_4$ at low temperature.
