Natasha Alechina, Dmitry Shkatov. Logics with an existential modality. In Guido Governatori, Ian M. Hodkinson, Yde Venema, editors, Advances in Modal Logic 6, papers from the sixth conference on Advances in Modal Logic, held in Noosa, Queensland, Australia, on 25-28 September 2006. pages 31-48, College Publications, 2006. [doi]
Abstract is missing.