Bicentric quadrilateral (English Wikipedia)

Yun, Zhang, "Euler's Inequality Revisited", Mathematical Spectrum, Volume 40, Number 3 (May 2008), pp. 119-121. First page available at [1] Archived March 4, 2016, at the Wayback Machine.

archive.org

Alsina, Claudi; Nelsen, Roger (2009). When less is more: visualizing basic inequalities. Mathematical Association of America. pp. 64–66. ISBN 978-0-88385-342-9.

cut-the-knot.org

Bogomolny, Alex, Collinearity in Bicentric Quadrilaterals [9], 2004.

doi.org

Salazar, Juan Carlos (2006), "Fuss's Theorem", Mathematical Gazette, 90 (July): 306–307, doi:10.1017/S002555720017980X.
Byerly, W. E. (1909), "The In- and-Circumscribed Quadrilateral", The Annals of Mathematics, 10 (3): 123–128, doi:10.2307/1967103, JSTOR 1967103.

emich.edu

math.emich.edu

Calin, Ovidiu, Euclidean and Non-Euclidean Geometry a metric approach, [8], pp. 153–158.

emis.de

Radic, Mirko, "Certain inequalities concerning bicentric quadrilaterals, hexagons and octagons", Journal of Inequalities in Pure and Applied Mathematics, Volume 6, Issue 1, 2005, [6]

fau.edu

forumgeom.fau.edu

Josefsson, Martin (2010), "Characterizations of Bicentric Quadrilaterals" (PDF), Forum Geometricorum, 10: 165–173.
Josefsson, Martin (2010), "Calculations concerning the tangent lengths and tangency chords of a tangential quadrilateral" (PDF), Forum Geometricorum, 10: 119–130, archived from the original (PDF) on August 13, 2011, retrieved August 19, 2011.
Josefsson, Martin (2011), "The Area of a Bicentric Quadrilateral" (PDF), Forum Geometricorum, 11: 155–164, archived from the original (PDF) on January 5, 2020, retrieved October 20, 2011.
Josefsson, Martin (2012), "Maximal Area of a Bicentric Quadrilateral" (PDF), Forum Geometricorum, 12: 237–241, archived from the original (PDF) on December 5, 2022, retrieved October 23, 2012.
Josefsson, Martin (2012), "A New Proof of Yun's Inequality for Bicentric Quadrilaterals" (PDF), Forum Geometricorum, 12: 79–82, archived from the original (PDF) on December 31, 2019, retrieved June 23, 2012.
Hess, Albrecht (2014), "On a circle containing the incenters of tangential quadrilaterals" (PDF), Forum Geometricorum, 14: 389–396, archived from the original (PDF) on December 14, 2014, retrieved December 15, 2014.
Shattuck, Mark, “A Geometric Inequality for Cyclic Quadrilaterals”, Forum Geometricorum 18, 2018, 141-154. [7] Archived September 13, 2018, at the Wayback Machine This paper also gives various inequalities in terms of the arc lengths subtended by a cyclic quadrilateral’s sides.

math.fau.edu

Yiu, Paul, Euclidean Geometry, [4] Archived March 2, 2019, at the Wayback Machine, 1998, pp. 158-164.

geometry.ru

Alexey A. Zaslavsky, One property of bicentral quadrilaterals, 2019, [11]

jstor.org

Byerly, W. E. (1909), "The In- and-Circumscribed Quadrilateral", The Annals of Mathematics, 10 (3): 123–128, doi:10.2307/1967103, JSTOR 1967103.

lvnaga.wordpress.com

L. V. Nagarajan, Bi-centric Polygons, 2014, [10].

uni-magdeburg.de

hydra.nat.uni-magdeburg.de

Inequalities proposed in Crux Mathematicorum, 2007.[5]

web.archive.org

Yun, Zhang, "Euler's Inequality Revisited", Mathematical Spectrum, Volume 40, Number 3 (May 2008), pp. 119-121. First page available at [1] Archived March 4, 2016, at the Wayback Machine.
Josefsson, Martin (2010), "Calculations concerning the tangent lengths and tangency chords of a tangential quadrilateral" (PDF), Forum Geometricorum, 10: 119–130, archived from the original (PDF) on August 13, 2011, retrieved August 19, 2011.
Josefsson, Martin (2011), "The Area of a Bicentric Quadrilateral" (PDF), Forum Geometricorum, 11: 155–164, archived from the original (PDF) on January 5, 2020, retrieved October 20, 2011.
Yiu, Paul, Euclidean Geometry, [4] Archived March 2, 2019, at the Wayback Machine, 1998, pp. 158-164.
Josefsson, Martin (2012), "Maximal Area of a Bicentric Quadrilateral" (PDF), Forum Geometricorum, 12: 237–241, archived from the original (PDF) on December 5, 2022, retrieved October 23, 2012.
Josefsson, Martin (2012), "A New Proof of Yun's Inequality for Bicentric Quadrilaterals" (PDF), Forum Geometricorum, 12: 79–82, archived from the original (PDF) on December 31, 2019, retrieved June 23, 2012.
Hess, Albrecht (2014), "On a circle containing the incenters of tangential quadrilaterals" (PDF), Forum Geometricorum, 14: 389–396, archived from the original (PDF) on December 14, 2014, retrieved December 15, 2014.
Shattuck, Mark, “A Geometric Inequality for Cyclic Quadrilaterals”, Forum Geometricorum 18, 2018, 141-154. [7] Archived September 13, 2018, at the Wayback Machine This paper also gives various inequalities in terms of the arc lengths subtended by a cyclic quadrilateral’s sides.

wolfram.com

mathworld.wolfram.com

Weisstein, Eric W. "Poncelet Transverse." From MathWorld – A Wolfram Web Resource, [2]
Weisstein, Eric, Bicentric Quadrilateral at MathWorld, [3], Accessed on 2011-08-13.