Gauge invariance of DVCS off an arbitrary spin hadron: the deuteron target caseI.V. Anikin, R.S. Pasechnik, B. Pire and O.V. TeryaevEur. Phys. J. C, 72 7 (2012) 2055DOI: https://doi.org/10.1140/epjc/s10052-012-2055-5