You can, if you want, subscribe to multiple lists at the same time
using one email. If you want to do so, leave the subject
line blank. Then write the subscribe commands in the body of the message.
The email will look like:
After you have sent the email, the Listar program will send
you an email back, one for every list you requested subscription to,
requesting a confirmation of your subscribe request. After you have
sent back this confirmation email, Listar will send you an email again with
the confirmation that you have been subscribed to the list(s) (again,
one confirmation email for every list you are subscribed to now).