Before revision:  Recent work of Akbarpour and Li formalizes credibility as an auction desideratum, and prove that the only optimal, credible, strategyproof auction is the ascending price auction  (Akbarpour and Li, 2019).
After revision:  Recent work of Akbarpour and Li formalizes credibility as an auction desideratum, and prove that the only optimal, credible, strategyproof auction is the ascending price auction with reserves (Akbarpour and Li, 2019).