Keyless signature infrastructure and PKI : hash-tree signatures in pre- and post-quantum worldBuldas, Ahto; Laanoja, Risto; Truu, AhtoInternational journal of services technology and management2017 / p. 117-130 : ill https://doi.org/10.1504/IJSTM.2017.10002708 Journal metrics at Scopus Article at Scopus