  Recently, in Hilger et al. (2011) [1] QCD sum rules for chiral partners in
the open-charm meson sector have been presented at nonzero baryon net density
or temperature up to and including mass dimension 5. Referring to this, details
concerning the cancelation of infrared divergences are presented and important
technical and conceptional ingredients for an incorporation of four-quark
condensates beyond factorization and of other mass dimension 6 condensates are
collected.
