Battle of Dai Do, 30 April - 3 May 1968.
Erik B. Villard
<a rel="nofollow" class="external text" href="https://history.army.mil/html/books/091/91-15-1/cmhPub_91-15-1.pdf"><i>Combat Operations: Staying the Course, October 1967-September 1968</i></a> (PDF 29.6 MB) by Erik B. Villard (2017). Washington, D.C.: United States Army Center of Military History, p. 534, map 42.