Linearization of isometric embeddings between Banach spaces: an elementary approach
The author gives a very elementary and accessible proof of the celebrated result due to him and \textit{N. J. Kalton} [Stud. Math 159, No. 1, 121--141 (2003; Zbl 1059.46058)] that a separable Banach space that isometrically embeds into a Banach space \(Y\), also embeds linear isometrically into \(Y\).
scientific article; zbMATH DE number 6082491