Afzali Borujeni, Seyed Hadi, Hiu-Fai Law, and Malte Müller. “Infinite Gammoids”. The Electronic Journal of Combinatorics 22, no. 1 (March 6, 2015): P1.53. Accessed March 15, 2026. https://www.combinatorics.org/ojs/index.php/eljc/article/view/v22i1p53.