1. Simmons-Duffin S.We asked all 50 states about their contact tracing capacity. Here's What We Learned. NPRApr 28, 2020. https://www.npr.org/sections/health-shots/2020/04/28/846736937/we-asked-all-50-states-about-their-contact-tracing-capacity-heres-what-we-learne
2. Albrecht M., Aparicio-Navarro F., Arief B., et al. Joint statement of U.K. scientist working in the field of privacy and security.29 April 2020. (https://drive.google.com/file/d/1uB4LcQHMVP-oLzIIHA9SjKj1uMd3erGu/view)
3. Hinch R., Probert W., Nurtay A., et al. Effective configuration of digital contact tracing app: a report to NHSX. 16 April 2020https://045.medsci.ox.ac.uk/files/files/report-effective-app-configurations.pdf.
4. Privacy-preserving contact tracing. April 2020. (https://www.apple.com/covid19/contacttracing)