Letter from Keith M. Nightingale to Dennis J. Duncanson. Nightingale, a Captain in the Infantry who served as an advisor to a Vietnamese Ranger Battalion in the Long Kanh, Bien Hoa, Bing Tuy Phuoc Tuy Province areas, now currently an instructor in the Military Science Department, thanks Duncanson for his book, Government and Revolution in Vietnam, which Nightingale describes as a source of information and reference material. Nightingale offers his account of the events surrounding General Nguyen Chi Tanh - as mentioned by Duncanson on page 372 of his book- who Nightingale confirms as having perished in a battle on 28 June 1967. It is unclear from this letter whether it was written in May or June 1969.