Perfect systems
Compositio Mathematica, Tome 19 (1968) no. 2, p. 95-166
@article{CM_1968__19_2_95_0,
     author = {Mahler, Kurt},
     title = {Perfect systems},
     journal = {Compositio Mathematica},
     publisher = {P. Noordhoff N. V., Groningen},
     volume = {19},
     number = {2},
     year = {1968},
     pages = {95-166},
     zbl = {0168.31303},
     mrnumber = {239099},
     language = {en},
     url = {http://www.numdam.org/item/CM_1968__19_2_95_0}
}
Mahler, K. Perfect systems. Compositio Mathematica, Tome 19 (1968) no. 2, pp. 95-166. http://www.numdam.org/item/CM_1968__19_2_95_0/

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