@book{CIF_1972__6__1_0,
     author = {Halperin, Isra\"el},
     title = {Th\'eorie des espaces hilbertiens},
     series = {Cours de l'institut Fourier},
     publisher = {Institut des Math\'ematiques Pures - Universit\'e Scientifique et M\'edicale de Grenoble},
     number = {6},
     year = {1972},
     language = {fr},
     url = {http://archive.numdam.org/item/CIF_1972__6__1_0/}
}