1. A computer-implemented method of generating a request for cancellation of an accounting, the method comprising: generating an electronic message by a first application, the first application executing in a landscape of computer systems providing message-based services, wherein the message comprises an accounting cancellation package containing: an accounting cancellation entity identifying a first document that characterizes cancellation of an accounting, and identifying a type of a second document characterizing posting information previously sent and to be canceled; and a business transaction document reference package containing a reference entity identifying the second document; and initiating transmission of the message to a second application to request cancellation of the accounting.