Tomoyuki Yamada is Professor Emeritus at Hokkaido University. His main field of interest is philosophy of language, especially, speech act theory. He has published many papers on dynamic logics of speech acts in English, including “Logical dynamics of some speech acts that affect obligations and preferences” (Synthese, 2008, 165: 195–315, DOI 10.1007/s11229-008-9368-9). A list of his publication can be found at https://researchmap.jp/read0166943?lang=en.
Contact him at yamada@hokkaido.email.ne.jp