Gamma graph calculi for modal logicsMa, Minghui; Pietarinen, Ahti-VeikkoSynthese2018 / p. 3621–3650 : ill https://doi.org/10.1007/s11229-017-1390-3 Journal metrics at Scopus Article at Scopus Journal metrics at WOS Article at WOS To Peirce Hintikka's thoughtsPietarinen, Ahti-VeikkoLogica Universalis2019 / p. 241–262 https://doi.org/10.1007/s11787-018-0203-x Journal metrics at Scopus Article at Scopus Journal metrics at WOS Article at WOS