See H. S. M. Coxeter's review of Grünbaum (1960) in MR0125489: "It is unfortunate that the author uses, instead of 'kite', the name 'deltoid', which belongs more properly to a curve, the three-cusped hypocycloid."
Haruki, Hiroshi; Rassias, Themistocles M. (1998), "A new characteristic of Möbius transformations by use of Apollonius quadrilaterals", Proceedings of the American Mathematical Society, 126 (10): 2857–2861, doi:10.1090/S0002-9939-98-04736-4, JSTOR119083, MR1485479
Alsina, Claudi; Nelsen, Roger B. (2020), "Section 3.4: Kites", A Cornucopia of Quadrilaterals, The Dolciani Mathematical Expositions, vol. 55, Providence, Rhode Island: MAA Press and American Mathematical Society, pp. 73–78, ISBN978-1-4704-5312-1, MR4286138; see also antiparallelograms, p. 212
Alsina, Claudi; Nelsen, Roger B. (2020), "Section 3.4: Kites", A Cornucopia of Quadrilaterals, The Dolciani Mathematical Expositions, vol. 55, Providence, Rhode Island: MAA Press and American Mathematical Society, pp. 73–78, ISBN978-1-4704-5312-1, MR4286138; see also antiparallelograms, p. 212
Haruki, Hiroshi; Rassias, Themistocles M. (1998), "A new characteristic of Möbius transformations by use of Apollonius quadrilaterals", Proceedings of the American Mathematical Society, 126 (10): 2857–2861, doi:10.1090/S0002-9939-98-04736-4, JSTOR119083, MR1485479
Dunham, Douglas; Lindgren, John; Witte, Dave (1981), "Creating repeating hyperbolic patterns", in Green, Doug; Lucido, Tony; Fuchs, Henry (eds.), Proceedings of the 8th Annual Conference on Computer Graphics and Interactive Techniques, SIGGRAPH 1981, Dallas, Texas, USA, August 3–7, 1981, Association for Computing Machinery, pp. 215–223, doi:10.1145/800224.806808, ISBN0-89791-045-1
Haruki, Hiroshi; Rassias, Themistocles M. (1998), "A new characteristic of Möbius transformations by use of Apollonius quadrilaterals", Proceedings of the American Mathematical Society, 126 (10): 2857–2861, doi:10.1090/S0002-9939-98-04736-4, JSTOR119083, MR1485479