Box integrals with fermion bubbles for low-energy measurements of the weak mixing angle Nico Böttcher, Niklas Schwanemann and Stefan Weinzierl Eur. Phys. J. C, 84 5 (2024) 495 Published online: 14 May 2024 DOI: 10.1140/epjc/s10052-024-12843-1