Sound effects used in this game:

Sound			Author			Link								License
Moving trap slam	CosmicD			http://freesound.org/people/CosmicD/sounds/132996/		CC BY 3.0
Moving trap retract	Doctor_Jekyll		http://freesound.org/people/Doctor_Jekyll/sounds/254064/	CC BY 3.0
Button ticking		coobek			http://freesound.org/people/coobek/sounds/185611/		CC0 1.0
Button press		bubaproducer		http://freesound.org/people/bubaproducer/sounds/107139/		CC BY 3.0
Box collisions 		zaneclampett		http://freesound.org/people/zaneclampett/sounds/263620/		CC0 1.0
Portal fail sound	aust_paul		http://freesound.org/people/aust_paul/sounds/30935/		CC0 1.0
Level end door closing	nichols8917		http://freesound.org/people/nichols8917/sounds/339632/		CC0 1.0	
Box destroying lasers	Supraliminal		http://freesound.org/people/Supraliminal/sounds/77172/		CC0 1.0
Portal opening		Rhulk			http://freesound.org/people/Rhulk/sounds/245460/		CC0 1.0
Portal ambient		shiversmedia		http://freesound.org/people/shiversmedia/sounds/254131/		CC BY 3.0

CC BY 3.0 - https://creativecommons.org/licenses/by/3.0/
CC0 1.0 - https://creativecommons.org/publicdomain/zero/1.0/