Resume of manned experiments. AMRL-TR-66-120.
D018504:Ecological Systems, Closed; D006371:Helium / Q000633:toxicity; D006801:Humans; D009584:Nitrogen / Q000633:toxicity; D010100:Oxygen / Q000633:toxicity; D013026:Space Flight
D006371:Helium; D009584:Nitrogen; D010100:Oxygen