[Mailman-Users] restrict subscription, unsubscription and send mails in mailman list

Hi everyone: I just arrived to this list and I'm needing your help. I have a mailman list and I need 3 things (I couldn't find this in google and in http://wiki.list.org/DOC/Frequently%20Asked%20Questions): 1- I need that the users couldn't subscribe to the list 2- I need that the subscribed users can't unsubscribe 3- I need that just some users can send mails to the list

Regards and Thanks in advance, Amaury. Noviembre 13-14: Final Caribeña 2015 del Concurso de Programación ACM-ICPC https://icpc.baylor.edu/regionals/finder/cf-2015