On Grothendieck universes
Compositio Mathematica, Volume 21 (1969) no. 1, p. 1-3 
@article{CM_1969__21_1_1_0,
     author = {Williams, N. H.},
     title = {On Grothendieck universes},
     journal = {Compositio Mathematica},
     publisher = {Wolters-Noordhoff Publishing},
     volume = {21},
     number = {1},
     year = {1969},
     pages = {1-3},
     zbl = {0175.00701},
     mrnumber = {244035},
     language = {en},
     url = {http://www.numdam.org/item/CM_1969__21_1_1_0}
}

Williams, N. H. On Grothendieck universes. Compositio Mathematica, Volume 21 (1969) no. 1, pp. 1-3. http://www.numdam.org/item/CM_1969__21_1_1_0/

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