Directed Percolation: Calculation of Feynman Diagrams in the Three-Loop Approximation Loran Ts. Adzhemyan, Michal Hnatič, Mikhail V. Kompaniets, Tomáš Lučivjanský and Lukáš Mižišin EPJ Web Conf., 173 (2018) 02001 Published online: 14 February 2018 DOI: 10.1051/epjconf/201817302001