Tolong jelaskan mengenai Bacaan lebih lanjut dari Resimen Infanteri ke-21 (Amerika Serikat)

Humphries, James F. (2008). Through the Valley: Vietnam, 1967-68. Mechanicsburg: Stackpole. .

Veatch, Paul D. (2000). Jungle, Sea, and Occupation: A World War II Soldier's Memoir of the Pacific Theater. Jefferson: McFarland. .