Original sentence: Members of the Harvard Negotiation Project, Fisher and Ulry focused on the psychology of negotiation in their method, "principled negotations", finding acceptable compromise by determining which needs are fixed and which flexible for negotiators
Edited sentence: Members of the Harvard Negotiation Project, Fisher and Ury focused on the psychology of negotiation in their method, "principled negotations", finding acceptable compromise by determining which needs are fixed and which flexible for negotiators