An excerpt from a biography of Mel H. Nesteby posted on the website of an organization known as the "American Ex-Prisoners of War Organization":
Mel enlisted in the Army on 17 May, 1941,.at Fargo, N.D. He chose a warm part of the world, in contrast to the frigid temperatures of Alaska, in which to serve, and the Philippine Islands over the Panama Canal Zone. Since he had been driving a big Caterpillar tractor in his farm work, he figured that he would be qualified for operating a tank. At Fort Snelling, near St. Paul, Minn., Mel was sworn into the Army. Mel and some other recruits attended a service at a nearby Methodist Church. Each young man was presented a pocket-sized New Testament. This little book was a divine gift, with a significance far beyond expectations. It sustained Mel through all his trials in the coming years. Not only that , but it brought the presence of Jesus to men who had reached the final hours of their lives: men so sick and so destitute that they were beyond recovery. This little Bible was confiscated by the Japanese at the time of surrender; but miraculously, it was returned to Mel. On its second page, it bears the stamp of the Japanese Imperial Army censor, with a date line inserted, and it is a sacred keepsake today.
Houston Baptist University has a Bible Museum. If you will scroll down this post, you will find an article entitled "A Veteren's Day Look at Soldier Bibles" that discusses them in earlier wars.
See also this history of the Pocket New Testament League.
And find the pocket New Testament reference in this amazing story of WW II.