no. 3
Comparing modules of differential operators by their evaluation on polynomials
Compositio Mathematica, Tome 69 (1989) no. 3, pp. 295-307. 
@article{CM_1989__69_3_295_0,
     author = {Hauser, Herwig},
     title = {Comparing modules of differential operators by their evaluation on polynomials},
     journal = {Compositio Mathematica},
     pages = {295--307},
     publisher = {Kluwer Academic Publishers},
     volume = {69},
     number = {3},
     year = {1989},
     zbl = {0693.32001},
     mrnumber = {985917},
     language = {en},
     url = {www.numdam.org/item/CM_1989__69_3_295_0/}
}
Hauser, Herwig. Comparing modules of differential operators by their evaluation on polynomials. Compositio Mathematica, Tome 69 (1989) no. 3, pp. 295-307. http://www.numdam.org/item/CM_1989__69_3_295_0/

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