Personal communication is not included in the reference list as it cannot be retrieved. You only refer to it in-text.
In-Text citations
You do not use a superscript number for personal communication, but place the following information in parentheses:
(Name of person, the person's highest qualification if known/relevant, form of communication, Month DD, YYYY)
e.g.:
The clinic changed opening hours in 2020 (L. Susanto, MD, email, April 12, 2023).
If the person's name is mentioned in the sentence, omit the name from the pattern:
Lisa Susanto, MD, stated the clinic changed opening hours in 2020 (email, April 12, 2023).
You can include all of the relevant details in the sentence and omit the parentheses entirely:
According to an email from Doctor Lisa Susanto, MD, in April 2023, the clinic changed opening hours in 2020.
Initial or name?
When using a person's name in your sentence, you should give their given name and middle initial the first time you refer to them, if these details are known. Give the initials if the full name is not known:
Lisa Susanto stated...
Lisa M. Susanto stated...
L. M. Susanto stated...
Subsequent references to the same person can give surname only:
Susanto also noted...
In the parentheses, use the initials instead of a given name:
(L. M. Susanto...)
(L. Susanto...)
