An important' tax question arises when income is received by a decedent's successor in interest as a result of a sale transaction which had its origins in the decedent's lifetime activities but which was not consummated until after his death. The answer to be sought is whether or not the proceeds of the sale constitute income in respect of a decedent within the meaning of section 6913 of the Internal Revenue Code of 1954. If so, the successor in interest will include in gross income the same amo