All the content created at Commune is free for use to everyone, you are free to use, adapt, redistribute this work without any need to give any credit.
However, it is good being graceful, as sometime different authors contribute on the website, sometime it is generally gracious to give credit/acknowledgement to me people.
Globally, such a attribution in the world has been recognized under Creative Common license 1.0 Universal. So, it can also be said that everything at Commune is under Creative Common license.