Sign. According to official website of Shanghai Jiaotong University, the recommendation letter from Shanghai Jiaotong University needs the signatures of at least two referees, one of whom must be the applicant's tutor. Therefore, if you want to apply for a doctorate from Shanghai Jiaotong University, you need at least one recommender to provide a letter of recommendation and sign it. Shanghai Jiaotong University, referred to as "Shanghai Jiaotong University", is located in Shanghai, a municipality directly under the Central Government. It is one of the oldest institutions of higher learning in China, a national key university directly under the Ministry of Education, co-founded with Shanghai and directly under the central government.