Mendoza Casas, JoséPakhrou, Tijani2023-06-202023-06-202003-06-010022-247X10.1016/S0022-247X(03)00169-0https://hdl.handle.net/20.500.14352/50162We study some characterizations of inner product spaces given in the literature. Among other things, we give an example showing that one of the characterizations given in the classical book of Amir (1986) is not correct.engjournal articlehttp://www.sciencedirect.com/science/article/pii/S0022247X03001690http://www.sciencedirect.com/science/restricted access517.518.826Chebyshev radiusinner product spaceAnálisis numérico1206 Análisis Numérico