A geometric characterization of the Radon-Nikodym property in Banach spaces
Compositio Mathematica, Volume 36 (1978) no. 1, p. 3-6 
@article{CM_1978__36_1_3_0,
     author = {Bourgain, Jean},
     title = {A geometric characterization of the Radon-Nikodym property in Banach spaces},
     journal = {Compositio Mathematica},
     publisher = {Sijthoff et Noordhoff International Publishers},
     volume = {36},
     number = {1},
     year = {1978},
     pages = {3-6},
     zbl = {0378.46017},
     mrnumber = {515034},
     language = {en},
     url = {http://www.numdam.org/item/CM_1978__36_1_3_0}
}

Bourgain, J. A geometric characterization of the Radon-Nikodym property in Banach spaces. Compositio Mathematica, Volume 36 (1978) no. 1, pp. 3-6. http://www.numdam.org/item/CM_1978__36_1_3_0/

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