become dominant over previous ones due to stronger network effects and the lack of acceptance of previous cryptocurrencies as a medium of payment \[sub:On-Network-Effects\].

-   Finally, the lower costs of its infrastructure imply the existence of a unique equilibrium where it dominates other forms of payment \[sub:Dominance-over-Cash\].

Related Literature
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This section discusses how the present paper is significantly better and more innovative than previous approaches in order to fulfill the objective of providing a Sybil-resistant and permissionless blockchain with anonymous transaction processing nodes (i.e., miners). Moreover, it’s considerably cheaper than other approaches[@coconut; @pop] that would require the re-identification and issuing of new identities to the global population because the current proposal relies on the previously issued credentials of electronic national identity cards (3.5 billion issued at the time of publication) and electronic passports (1 billion issued at the time of publication).

Proof of Space[@cryptoeprint:2013:796; @cryptoeprint:2013:805] reduces the energy costs of Proof-of-Work but it’s not economically efficient. Proof of Authority[@poa](PoA) maintains a public list of previously authorised nodes: the identities are not anonymised and the blockchain is not open to everyone (i.e., the blockchain is permissioned). Proof of Personhood[@pop](PoP) can be understood as an improvement over Proof of Authority in 