Competition graphs of degree bounded digraphs. - Hojin Chu; Suh-Ryung Kim (Discret. Appl. Math., 2024)

A digraph version of the Friendship Theorem. - Myungho Choi; Hojin Chu; Suh-Ryung Kim (Discret. Math., 2025)

Digraphs in which every t vertices have exactly λ common out-neighbors. - Myungho Choi; Hojin Chu; Suh-Ryung Kim (Discret. Math., 2025)