no. 1
Riemann surfaces and spin structures
Annales scientifiques de l'École Normale Supérieure, Série 4, Tome 4 (1971) no. 1, pp. 47-62. 
@article{ASENS_1971_4_4_1_47_0,
     author = {Atiyah, Michael F.},
     title = {Riemann surfaces and spin structures},
     journal = {Annales scientifiques de l'\'Ecole Normale Sup\'erieure},
     pages = {47--62},
     publisher = {Elsevier},
     volume = {Ser. 4, 4},
     number = {1},
     year = {1971},
     doi = {10.24033/asens.1205},
     zbl = {0212.56402},
     mrnumber = {44 \#3350},
     language = {en},
     url = {www.numdam.org/item/ASENS_1971_4_4_1_47_0/}
}
Atiyah, Michael F. Riemann surfaces and spin structures. Annales scientifiques de l'École Normale Supérieure, Série 4, Tome 4 (1971) no. 1, pp. 47-62. doi : 10.24033/asens.1205. http://www.numdam.org/item/ASENS_1971_4_4_1_47_0/

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