A Dyson–Schwinger study of the four-gluon vertex Anton K. Cyrol, Markus Q. Huber and Lorenz von Smekal Eur. Phys. J. C, 75 3 (2015) 102 Published online: 04 March 2015 DOI: 10.1140/epjc/s10052-015-3312-1