Acta Physica SinicaTHE INTERACTION PICTURE IN THE CLOSED TIME PATH GREEN'S FUNCTIONSXU HONG-HUA, 上海市普陀区业余大学Published Jan 1, 1985• 0 citationsPublisherAbstractIt is clarified that the interaction picture introduced in CTPGF ought to be the incoming one and the perturbation expansion of CTPGF to be developed also in this sense.DOI10.7498/aps.34.1359