{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,11]],"date-time":"2025-12-11T20:58:43Z","timestamp":1765486723716,"version":"build-2065373602"},"reference-count":37,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,2,24]],"date-time":"2022-02-24T00:00:00Z","timestamp":1645660800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Axioms"],"abstract":"<jats:p>In this paper, we introduce and investigate new subclasses (Yamakawa-type bi-starlike functions and another class of Lashin, both mentioned in the reference list) of bi-univalent functions defined in the open unit disk, which are associated with the Gegenbauer polynomials and satisfy subordination conditions. Furthermore, we find estimates for the Taylor\u2013Maclaurin coefficients |a2| and |a3| for functions in these new subclasses. Several known or new consequences of the results are also pointed out.<\/jats:p>","DOI":"10.3390\/axioms11030092","type":"journal-article","created":{"date-parts":[[2022,2,24]],"date-time":"2022-02-24T07:22:35Z","timestamp":1645687355000},"page":"92","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Subclasses of Yamakawa-Type Bi-Starlike Functions Associated with Gegenbauer Polynomials"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8285-6619","authenticated-orcid":false,"given":"Gangadharan","family":"Murugusundaramoorthy","sequence":"first","affiliation":[{"name":"Department of Mathematics, School of Advanced Sciences, Vellore Institute of Technology, Vellore 632014, TN, India"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8026-218X","authenticated-orcid":false,"given":"Teodor","family":"Bulboac\u0103","sequence":"additional","affiliation":[{"name":"Faculty of Mathematics and Computer Science, Babe\u015f-Bolyai University, 400084 Cluj-Napoca, Romania"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"219","DOI":"10.1186\/1687-1847-2012-219","article-title":"Some identities involving Gegenbauer polynomials","volume":"2012","author":"Kim","year":"2012","journal-title":"Adv. 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