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

[1] A. Borel and H. Jacquet: Automorphic forms and automorphic representations. Proc. of Symp. in Pure Math. 33 (1979) 189-202. | MR 546598 | Zbl 0414.22020

[2] A. Borel: Linear algebraic groups. Proc. of Symp. in Pure Math. 9 (1966) 3-19. | MR 204532 | Zbl 0205.50503

[3] A. Borel: Reduction theory for arithmetic groups. Proc. of Symp. in Pure Math. 9 (1966), 20-25. | MR 204533 | Zbl 0213.47201