no. 2
On the maximal distance between integers composed of small primes
Compositio Mathematica, Tome 28 (1974) no. 2, pp. 159-162. 
@article{CM_1974__28_2_159_0,
     author = {Tijdeman, Robert},
     title = {On the maximal distance between integers composed of small primes},
     journal = {Compositio Mathematica},
     pages = {159--162},
     publisher = {Noordhoff International Publishing},
     volume = {28},
     number = {2},
     year = {1974},
     zbl = {0283.10024},
     mrnumber = {345917},
     language = {en},
     url = {archive.numdam.org/item/CM_1974__28_2_159_0/}
}
Tijdeman, R. On the maximal distance between integers composed of small primes. Compositio Mathematica, Tome 28 (1974) no. 2, pp. 159-162. http://archive.numdam.org/item/CM_1974__28_2_159_0/

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