reference for future work in this subject) and readable if we give rather complete details.

This paper would not exist without the insight and guidance of Peter Sarnak who suggested Gergely Harcos in 2000 to work on this project; we are grateful for his support over the years. Important parts of this paper were written during a visit of Valentin Blomer to Rényi Institute of Mathematics in October 2008, and during the workshop “Analytic Theory of GL(3) Automorphic Forms and Applications" at the American Institute of Mathematics in November 2008. We thank both institutions for their hospitality and financial support, and the organizers of the workshop for their kind invitation. Finally we thank Jim Arthur for valuable discussions related to this work.

Part I: Background on automorphic forms {#section2}
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Basic Notation
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### Number fields and adele rings {#numberfields}

Let $K$ be a totally real number field over ${\mathbb{Q}}$ of degree $d$, discriminant $D_K$, different $\mathfrak{d}$ and ring of integers ${\mathfrak{o}}$. Throughout the paper we regard $K$ as fixed and all constants may depend on $K$, even if not stated explicitly, and they may also depend on ${\varepsilon}$ which denotes an arbitrarily small positive number, not necessarily the same 