The palm is Nenga banaensis (Magalon) Burret, or "cây cau rung" as it's known in central Vietnam. The first botanist is Dr. Andrew Henderson (see An Unusual Rattan and Pressing Plectocomiopsis), a palm specialist in the Institute of Systematic Botany of The New York Botanical Garden. The second botanist is Mr. Biu Van Thanh (see Kon Tum and Phong Dien), a doctoral student at the Vietnamese Institute of Ecology and Biological Resources (IEBR) in Hanoi. [NOTE: I like their hats.]