Summarize
Item 1: A personal letter from an unidentified infiltrator to his elder brother ((in NVN)), reads in part as follows: "On 13 Apr 70, I arrived at Assembly Area Quang Trung of B2 ((Front)) in Cambodia. After that, I was so busy building the base area that I did not have time to write to you. Today ((no further information )), I am taking advantage of free time to write this letter to you in care of Ngoan, who is to proceed to NVN soon. Have you received the letters that I sent to you w—.