Management: Tasks, Responsibilities, Practices (1974) by Peter F. Drucker is a good source for understanding managerial communication in practice. Drucker gives chapter 38 in his book the title "Managerial Communication." There is, however, a lot of variation in stakeholders' views concerning the communication skills business school graduate will need when they start working.
Every principles of management textbook I've used over the years includes a chapter on communication competency. Nevertheless, there seems to be no real agreement on exactly what communication skills are needed in relation to the functional areas of planning, organizing, leading, and controlling.
Therefore, what communication skills are needed to function in planning, organizing, leading and controlling?