/usr/include/ is in libceres-dev 1.13.0+dfsg0-2.
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/usr/include/ceres/
/usr/include/ceres/autodiff_cost_function.h
/usr/include/ceres/autodiff_local_parameterization.h
/usr/include/ceres/c_api.h
/usr/include/ceres/ceres.h
/usr/include/ceres/conditioned_cost_function.h
/usr/include/ceres/cost_function.h
/usr/include/ceres/cost_function_to_functor.h
/usr/include/ceres/covariance.h
/usr/include/ceres/crs_matrix.h
/usr/include/ceres/cubic_interpolation.h
/usr/include/ceres/dynamic_autodiff_cost_function.h
/usr/include/ceres/dynamic_cost_function.h
/usr/include/ceres/dynamic_cost_function_to_functor.h
/usr/include/ceres/dynamic_numeric_diff_cost_function.h
/usr/include/ceres/fpclassify.h
/usr/include/ceres/gradient_checker.h
/usr/include/ceres/gradient_problem.h
/usr/include/ceres/gradient_problem_solver.h
/usr/include/ceres/internal/
/usr/include/ceres/internal/autodiff.h
/usr/include/ceres/internal/config.h
/usr/include/ceres/internal/disable_warnings.h
/usr/include/ceres/internal/eigen.h
/usr/include/ceres/internal/fixed_array.h
/usr/include/ceres/internal/macros.h
/usr/include/ceres/internal/manual_constructor.h
/usr/include/ceres/internal/numeric_diff.h
/usr/include/ceres/internal/port.h
/usr/include/ceres/internal/reenable_warnings.h
/usr/include/ceres/internal/scoped_ptr.h
/usr/include/ceres/internal/variadic_evaluate.h
/usr/include/ceres/iteration_callback.h
/usr/include/ceres/jet.h
/usr/include/ceres/local_parameterization.h
/usr/include/ceres/loss_function.h
/usr/include/ceres/normal_prior.h
/usr/include/ceres/numeric_diff_cost_function.h
/usr/include/ceres/numeric_diff_options.h
/usr/include/ceres/ordered_groups.h
/usr/include/ceres/problem.h
/usr/include/ceres/rotation.h
/usr/include/ceres/sized_cost_function.h
/usr/include/ceres/solver.h
/usr/include/ceres/types.h
/usr/include/ceres/version.h