What does GSA stand for?

In deference to the weakness of the Vietnamese Artillery (six 105-mm howitzers and six 155-mm howitzers), the agreement specifically provided that 4th Infantry Division Artillery units would assume artillery coverage of National Highway 14, the major north-south artery in the highlands, and that the Commanding General, IFF Artillery, would provide general support Artillery as required; support operations within the 24th STZ with a minimum of two light or medium Artillery batteries; and maintain the fire support coordination center to coordinate all fire support means available, including operation of air advisory stations.