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2. ANSI, Dimensioning and Tolerancing, ASME+Y14.5-2009.
3. Circle fitting from the polarity transformation regression;Calvo;Prec. Eng.,2013
4. Does the best fit always exist?;Chernov;ISRN Probab. Stat.,2012
5. Is the best fitting curve always unique?;Chernov;J. Math.,2013