Geodesic
On an extreme point conjecture for concave functions
Izvestiâ vysših učebnyh zavedenij. Matematika, no. 12 (2011), pp. 54-58 Cet article a éte moissonné depuis la source Math-Net.Ru

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Let $\mathrm{CO}(A)$, $A\in(1,2]$, denote the family of concave univalent functions in the unit disk $\mathbb D$ with opening angle at infinity bounded by $\pi A$. We prove a weak form of a conjecture on the extreme points of $\mathrm{clco\,CO}(A)$ from the paper in Indian J. Math. 50, 339–349 (2008).
Keywords: concave univalent functions, starlike functions, extreme points. 
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S. Ponnusamy; K.-J. Wirths. On an extreme point conjecture for concave functions. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 12 (2011), pp. 54-58. http://geodesic.mathdoc.fr/item/IVM_2011_12_a5/

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