FOUR journal articles, all published in 1930s on various topics relating to high altitude and health/medical/metabolic conditions.  

Item 1: 

"Individual Variations in Ability to Acclimatize to High Altitude."  Research paper originally published by Royal Society of London. Conducted by researchers at Harvard and Columbia Universities.  (See images for names of authors.) 

Individual article reprinted from Proceedings of the Royal Society of London, Series B No 842, vol. 126 pp. 1-29, September 1938.  34 pages, 6.75" x 10", illustrated with charts and graphs.  

Item 2: 

"Physiology of Life at High Altitudes: International High Altitude Expedition to Chile, 1935."

Dr. Ancel Keys, Organizer and Manager of Expedition and Assistant Professor of Biochemistry, The Mayo Foundation for Medical Research.  12 pages. Very good condition. Reprinted from The Scientific Monthly, Vol XLIII, pages 289-312.  

Item 3: 

"Blood Sugar and Glucose Tolerance at High Altitudes." W.H. Forbes from the Fatigue Laboratory, Harvard University. Reprinted from the American Journal of Physiology, Vol 116, No. 2, July, 1936. 

Item 4: 

"The Metabolism of Alcohol in Man at High Altitudes." R.A. McFarland and W.H. Forbes from the Department of Psychology, Columbia University and the Fatigue Laboratory, Harvard University.  Reprinted from Human Biology, September 1936, Johns Hopkins Press, Baltimore.  (From a quick read it looks like the authors were also the subjects of the study...so I'm not sure what that might mean for the accuracy of or the validity of the research given significant amounts of alcohol were involved.  

 :-)  

Four separate articles/books.  Complete and in very good condition.  All published circa 1935-1938.