© p0ss : rosted metal texture pack for the upgrade_center and the ship_factory | http://opengameart.org/node/4778
and 
© equalypse : beta 04 (here:beta_01) | http://www.jamendo.com/de/album/85869
Both are licensed under CC-BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0/)

Licensed under CC-BY-SA 3.0
© following files from Stephen M. Cameron (http://sourceforge.net/users/smcameron | http://opengameart.org/content/action-shooter-soundset-wwvi)
units/rocket_turret/sounds/volcano_eruption_edit.wav
units/rocket_turret/sounds/synthetic_laser.wav

units/laser_tank/sounds/rifleprimary2.ogg
License cc-by-sa 3.0
© Skorpio

