According to the APA Manual (6th edition), personal communications only need to be cited in-text. They do not have to be on your reference list unless your professor specifies other. For the in-text citation, the elements you need to include are the first initials and last name of the communicator and the exact date of the communication. Below are two examples:
J.D. Jones (personal communication, August 26, 2015)
(A.K. Smith, personal communication, September 23, 2015)