Rhythmbox Developer Contact

My name is Sulaiman The WordSmith. I am writing here because I writing a
book titled about digitally distributing music and the book utilizes
Rhythmbox art work. I have attempted to get in touch with the developers of
Rhythmbox several times for there opinion of the book and permission use the
art work. I am aware that Rhythmbox comes with the GNU/GPL license and I cud
use the artwork with out the developers direct consent. But I would prefer
that they be informed. Does any one know how to get in touch with the
developers of Rhythmbox? Contact me at "info822 [at] thewordsmith.info".