CONF Sajadmanesh_USENIXSECURITY_2023/IDIAP GAP: Differentially Private Graph Neural Networks with Aggregation Perturbation Sajadmanesh, Sina Shamsabadi, Ali Shahin Bellet, Aurélien Gatica-Perez, Daniel EXTERNAL https://publications.idiap.ch/attachments/papers/2022/Sajadmanesh_USENIXSECURITY_2023.pdf PUBLIC 32nd USENIX Security Symposium (USENIX Security 23) 2023