PPCT: Privacy-Preserving Contact Tracing Using Concise Private Set Intersection Cardinality. - Qianheng Yang; Yuer Yang; Shiyuan Xu; Rongrong Guo; Huiguang Xian; Yifeng Lin; Xue Chen; Wuzheng Tan; Siu-Ming Yiu (J. Netw. Syst. Manag., 2024)