|Live events include interviews and class lectures.|
Proper Bibliographic Reference Format:
Because the information contained in emails, interviews and class lectures is not retrievable and thus cannot be verified by readers, treat emails, interviews and class lectures as personal communication.
Give the initials as well as the surname of the communicator, and provide as exact a date as possible:
...(D. M. Haybron, personal communication, January 10, 2009)
Alternatively, you can integrate the citation into the sentence by means of narrative:
D. M. Haybron (personal communication, January 10, 2009) noted that...