  The covariant parton model is generalized to describe quark correlators in a
systematic way. Previous results are reproduced for the T-even leading-twist
transverse momentum dependent parton distribution functions (TMDs), and for the
first time all T-even twist-3 TMDs are evaluated in this model. We apply the
approach to evaluate the fully unintegrated quark correlator which allows us to
understand the model-specific relations between different TMDs. We verify the
consistency of the approach, present numerical results and compare to available
TMD parametrizations.
