Anstee, R. P., and Santiago Salazar. “Forbidden Berge Hypergraphs”. The Electronic Journal of Combinatorics 24, no. 1 (March 31, 2017): #P1.59. Accessed May 15, 2026. https://www.combinatorics.org/ojs/index.php/eljc/article/view/v24i1p59.