BibTeX field type: email
Email includes the email address of the stated authors if you want to indicate them. It's not a common field and might not be supported.
To specify email addresses, the following variants are recommended:
As a note to display at the end of the reference:
@book{ ... ,
author = {Muller, John},
...
note = "{\tt john.muller@example.com}"
}
To display behind the family name:
@book{ ... ,
author = {Muller {\tt john.muller@example.com}, John },
...
}