%0 Journal Article %A Mouloud Goubi %T Series Expansion of a Cotangent Sum Related to the Estermann Zeta Function %J Kragujevac Journal of Mathematics %D 2021 %P 343 %V 45 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/KJM_2021_45_3_a1/ %G en %F KJM_2021_45_3_a1