\address{Return address}
The return address, as it should appear on the letter and the envelope.
Separate lines of the address should be separated by \\ commands.
If you do not make an \address declaration, then the letter will
be formatted for copying onto your organisation's standard letterhead.
(See section Overview of LaTeX and Local Guide, for details on your local implementation). If you
give an \address declaration, then the letter will be formatted
as a personal letter.