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• A practical software package for computing gravimetric geoid by the least squares modification of Hotine’s formulaAbbak, Ramazan Alpay; Ellmann, Artu; Ustun, AydinEarth science informatics2022 / p. 713-724 https://doi.org/10.1007/s12145-021-00713-3 https://www.scopus.com/sourceid/14500154730 https://www.scopus.com/record/display.uri?eid=2-s2.0-85117143319&origin=inward&txGid=bcc3fa2c65f6704f5dd54337665a13c9 https://jcr.clarivate.com/jcr-jp/journal-profile?journal=EARTH%20SCI%20INFORM&year=2022 https://www.webofscience.com/wos/woscc/full-record/WOS:000707544400002
• A precise gravimetric geoid model in a mountainous area with scarce gravity data : a case study in central TurkeyAbbak, Ramazan Alpay; Sjöberg, Lars E.; Ellmann, Artu; Ustun, AydinStudia geophysica et geodaetica2012 / p. 909-927 : ill https://link.springer.com/article/10.1007/s11200-011-9001-0