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The arbitrary order is suggested in the sense of Riemann-Liouville calculus.<\/jats:p>","DOI":"10.3390\/e17053172","type":"journal-article","created":{"date-parts":[[2015,5,13]],"date-time":"2015-05-13T12:42:07Z","timestamp":1431520927000},"page":"3172-3181","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":36,"title":["Existence of Ulam Stability for Iterative Fractional Differential Equations Based on Fractional Entropy"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9341-025X","authenticated-orcid":false,"given":"Rabha","family":"Ibrahim","sequence":"first","affiliation":[{"name":"Institute of Mathematical Sciences, University Malaya, Kuala Lumpur 50603, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4823-6851","authenticated-orcid":false,"given":"Hamid","family":"Jalab","sequence":"additional","affiliation":[{"name":"Faculty of Computer Science and Information Technology, University Malaya, Kuala Lumpur 50603, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,5,13]]},"reference":[{"key":"ref_1","unstructured":"Ulam, S.M. 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