no. 2
Extensions with restricted ramification and duality for arithmetic schemes
Compositio Mathematica, Tome 100 (1996) no. 2, pp. 233-245. 
@article{CM_1996__100_2_233_0,
     author = {Schmidt, Alexander},
     title = {Extensions with restricted ramification and duality for arithmetic schemes},
     journal = {Compositio Mathematica},
     pages = {233--245},
     publisher = {Kluwer Academic Publishers},
     volume = {100},
     number = {2},
     year = {1996},
     zbl = {0873.14027},
     mrnumber = {1383466},
     language = {en},
     url = {www.numdam.org/item/CM_1996__100_2_233_0/}
}
Schmidt, Alexander. Extensions with restricted ramification and duality for arithmetic schemes. Compositio Mathematica, Tome 100 (1996) no. 2, pp. 233-245. http://www.numdam.org/item/CM_1996__100_2_233_0/

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