Whenever a resource is not published and cannot be retrieved (in other words, does not have information needed for the source element) it is treated as a "personal communication." Examples of "personal communications" include:
Because the reader cannot retrieve the resource, an entry for the resource is not included in the References list. However, the resource is cited in the text of the paper following this format:
Note: The date provided in the in-text citation is the date that the communication took place.