The 1951 San Francisco Peace Treaty does not explicitly mention the Senkaku Islands. However Article I of US Civil Administration Ordinance No. 68, the Provisions of the Government of the Ryukyu Islands, gives the longitude and latitude within which the Ryukyu government was to have jurisdiction, and the Senkaku Islands are located within this area. The ordinance was announced on February 29, 1952, and implemented on April 1 of the same year. (Ref. 1)
Ref.1 ：Provisions of the Government of the Ryukyu Islands, Chapter 1 General, Article 1
(US Civil Administration Ordinance No. 68). Okinawa Prefectural Archives.
"Senkaku Retto dai 2 shu" (The Senkaku Islands Second Feature), in Kikan Okinawa (Okinawa Quarterly) 63 (December 31, 1972), p. 158.
Kikan Okinawa is the journal of Nanpo Doho Engokai (Assistance Association for Okinawa and Ogasawara Islands).
Japan's Island Territories
Senkaku Islands Facts & Figures
Takeshima Facts & Figures
Northern Territories Facts & Figures