Eduard Diepstraten Ruurd Kuiper Abadi & Lamport and Stark: towards a Proof Theory for Stuttering, Dense Domains and Refinement Mappings. 208-238 1989 conf/rex/1989 REX Workshop db/conf/rex/rex89.html#DiepstratenK89 http://dx.doi.org/10.1007/3-540-52559-9_66