@article{JEMS_2013_15_5_a7,
     author = {Valentin Blomer},
     title = {On the 4-norm of an automorphic form},
     journal = {Journal of the European Mathematical Society},
     pages = {1825--1852},
     year = {2013},
     volume = {15},
     number = {5},
     doi = {10.4171/jems/405},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/jems/405/}
}