[1] WHO. Interim guidance for developing a Smart Vaccination Certificate. https://cdn.who.int/media/docs/default-source/documents/interim-guidance-svc_20210319_final.pdf. [2021-11-11].
[2] Ma JQ. Perspectives: application of ‘Blockchain plus public health’. China CDC Wkly 2020;2(38):744 − 6. http://dx.doi.org/10.46234/ccdcw2020.201CrossRef
[3] Li F, Li ZR, Zhao H. Research on the progress in cross-chain technology of blockchains. J Softw 2019;30(6):1649 − 60. http://dx.doi.org/10.13328/j.cnki.jos.005741 (In Chinese). CrossRef
[4] Zhu Y, Gan GH, Deng D, Ji FF, Chen AP. Security architecture and key technologies of blockchain. J Inf Secur Res 2016;2(12):1090 − 7. http://dx.doi.org/10.3969/j.issn.2096-1057.2016.12.004 (In Chinese). CrossRef
[5] Yao ZJ, Ge JG. A summary of the theory and application of blockChain. E-Sci Technol Appli 2017;8(2):3 − 17. http://dx.doi.org/10.11871/j.issn.1674-9480.2017.02.001 (In Chinese). CrossRef
[6] W3C Working Group. Use Cases and Requirements for Decentralized Identifiers. https://www.w3.org/TR/2021/NOTE-did-use-cases-20210317/. [2021-11-11].https://www.w3.org/TR/2021/NOTE-did-use-cases-20210317/