{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2023,9,28]],"date-time":"2023-09-28T05:40:18Z","timestamp":1695879618316},"reference-count":2,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[2006,11,13]],"date-time":"2006-11-13T00:00:00Z","timestamp":1163376000000},"content-version":"vor","delay-in-days":5430,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Mathematical Logic Qtrly"],"published-print":{"date-parts":[[1992,1]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>C5.\u03c9 is obtained by adding, schematically, to the strict\u2010implicational fragment C5 of S5 the axiom ((<jats:italic>p<\/jats:italic> \u2192 <jats:italic>q<\/jats:italic>) \u2192 (<jats:italic>q<\/jats:italic> \u2192 <jats:italic>p<\/jats:italic>)) \u2192 (<jats:italic>q<\/jats:italic> \u2192 <jats:italic>p<\/jats:italic>). This paper presents a fully general proof that neither C5.\u03c9 nor any of a descending chain of its extensions is complete with respect to any class of frames, correcting the garbled details of a version skeched in an earlier paper (same Zeitschrift <jats:bold>31<\/jats:bold> (1985), 201\u2010208).<\/jats:p>","DOI":"10.1002\/malq.19920380129","type":"journal-article","created":{"date-parts":[[2007,5,29]],"date-time":"2007-05-29T05:42:30Z","timestamp":1180417350000},"page":"321-323","source":"Crossref","is-referenced-by-count":1,"title":["ON THE INCOMPLETENESS OF A DESCENDING CHAIN OF EXTENSIONS OF IMPLICATIONAL S5"],"prefix":"10.1002","volume":"38","author":[{"given":"Dolph","family":"Ulrich","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2006,11,13]]},"reference":[{"key":"e_1_2_1_2_2","volume-title":"Philosophical Logic","author":"Lemmon E. J.","year":"1969"},{"key":"e_1_2_1_3_2","first-page":"201","article-title":"A descending chain of incomplete extensions of implicational S5","volume":"31","author":"Ulrich D.","year":"1985","journal-title":"This Zeitschrift"}],"container-title":["Mathematical Logic Quarterly"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fmalq.19920380129","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/malq.19920380129","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,9,27]],"date-time":"2023-09-27T20:34:51Z","timestamp":1695846891000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/malq.19920380129"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1992,1]]},"references-count":2,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1992,1]]}},"alternative-id":["10.1002\/malq.19920380129"],"URL":"https:\/\/doi.org\/10.1002\/malq.19920380129","archive":["Portico"],"relation":{},"ISSN":["0942-5616","1521-3870"],"issn-type":[{"value":"0942-5616","type":"print"},{"value":"1521-3870","type":"electronic"}],"subject":[],"published":{"date-parts":[[1992,1]]}}}