Study of the contract for air-ground intermodal transport in private international law Study on the problems of nationality in private international law Study on the jurisdiction system concerning internet cases in private international law 并列题名：Study on the jurisdiction system concerning internet cases in private international law Study guarantee involving foreign elements in private international law Study of public order on private international law On the doctrine of the most significant relationship in private international law 并列题名：On the doctrine of the most significant relationship in private international law 并列题名：Study on the problems of nationality in private international law