Functional analysis / Selim Grigorʹevich Kreĭn ... [et al.] ; transl. from the Russian by Richard E. Flaherty ; English ed. ed. by George F. Votruba ; with the collab. of Leo F. BoronVector spaces / D.A. Raikov ; transl. from the 1st Russian ed. by Leo F. Boron ; with the assistance of Harlan R. Stevens and George F. Votruba