Foteini Baldimtsi, Aggelos Kiayias,  Thomas Zacharias and Bingsheng Zhang: “Indistinguishable Proofs of Work or Knowledge“.

Indistinguishable Proofs of Work or Knowledge (PoWorKs) constitute a novel class of interactive protocols where a prover can convince a verifier that she has either performed work or that she possesses knowledge of a witness to a public statement without the verifier being able to distinguish which of the two has taken place.