Remark on the definition of an automorphic form
Compositio Mathematica, Volume 59 (1986) no. 1, p. 3-13 
@article{CM_1986__59_1_3_0,
     author = {Averbuch, V.},
     title = {Remark on the definition of an automorphic form},
     journal = {Compositio Mathematica},
     publisher = {Martinus Nijhoff Publishers},
     volume = {59},
     number = {1},
     year = {1986},
     pages = {3-13},
     zbl = {0596.10024},
     mrnumber = {850116},
     language = {en},
     url = {http://www.numdam.org/item/CM_1986__59_1_3_0}
}

Averbuch, V. Remark on the definition of an automorphic form. Compositio Mathematica, Volume 59 (1986) no. 1, pp. 3-13. http://www.numdam.org/item/CM_1986__59_1_3_0/

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