Diameter problems for univalent functions with quasiconformal extension (Q689008)

The author utilizes ``the method of extremal length to study several diameter problems for functions conformal outside of a disc centred at the origin, with a standard normalization, which possess a quasiconformal extension to a ring subdomain of this disc''. As consequences of the results obtained, some known results are extended and some of their applications are given. [\textit{J. O. McLeavey} Trans. Am. Math. Soc. 195, 327-343 (1974; Zbl 0292.30017)].