The use of injective-like structures in model theory
Compositio Mathematica, Volume 28 (1974) no. 2, p. 113-142 
@article{CM_1974__28_2_113_0,
     author = {Simmons, H.},
     title = {The use of injective-like structures in model theory},
     journal = {Compositio Mathematica},
     publisher = {Noordhoff International Publishing},
     volume = {28},
     number = {2},
     year = {1974},
     pages = {113-142},
     zbl = {0291.02035},
     mrnumber = {351801},
     language = {en},
     url = {http://www.numdam.org/item/CM_1974__28_2_113_0}
}

Simmons, H. The use of injective-like structures in model theory. Compositio Mathematica, Volume 28 (1974) no. 2, pp. 113-142. http://www.numdam.org/item/CM_1974__28_2_113_0/

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