no. 1
A problem of D. H. Lehmer and its generalization (II)
Compositio Mathematica, Tome 91 (1994) no. 1, pp. 47-56. 
@article{CM_1994__91_1_47_0,
     author = {Wenpeng, Zhang},
     title = {A problem of D. H. Lehmer and its generalization (II)},
     journal = {Compositio Mathematica},
     pages = {47--56},
     publisher = {Kluwer Academic Publishers},
     volume = {91},
     number = {1},
     year = {1994},
     zbl = {0798.11001},
     mrnumber = {1273925},
     language = {en},
     url = {archive.numdam.org/item/CM_1994__91_1_47_0/}
}
Wenpeng, Zhang. A problem of D. H. Lehmer and its generalization (II). Compositio Mathematica, Tome 91 (1994) no. 1, pp. 47-56. http://archive.numdam.org/item/CM_1994__91_1_47_0/

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