K-regular factors and semi-k-regular factors in graphs. - Keiko Kotani (Discret. Math., 1998)

Factors and Connected Induced Subgraphs. - Keiko Kotani (Graphs Comb., 2001)

Nonseparating vertices in tournaments with large minimum degree. - Keiko Kotani (Australas. J Comb., 2006)

4-factors in 2-connected star-free graphs. - Yoshimi Egawa; Keiko Kotani (Discret. Math., 2009)

Existence of 4-factors in star-free graphs with high connectivity. - Yoshimi Egawa; Keiko Kotani (Australas. J Comb., 2013)

Uniform coverings of 2-paths with 4-cycles. - Midori Kobayashi; Keiko Kotani; Nobuaki Mutoh; Gisaku Nakamura (AKCE Int. J. Graphs Comb., 2015)

Structure of edges in a 4-connected graph not contained in triangles and the number of contractible edges. - Yoshimi Egawa; Keiko Kotani; Shunsuke Nakamura (AKCE Int. J. Graphs Comb., 2018)

Edges incident with a vertex of degree greater than four and a lower bound on the number of contractible edges in a 4-connected graph. - Shunsuke Nakamura; Yoshimi Egawa; Keiko Kotani (Electron. Notes Discret. Math., 2018)

Lower Bound on the Number of Contractible Edges in a 4-Connected Graph with Edges Not Contained in Triangles. - Yoshimi Egawa; Keiko Kotani; Shunsuke Nakamura (Graphs Comb., 2018)

Existence of 3-factors in K1, n-free graphs with connectivity and edge-connectivity conditions. - Keiko Kotani; Shuto Nishida (Australas. J Comb., 2021)

Existence of 4-factors in star-free graphs with edge-connectivity conditions. - Yoshimi Egawa; Keiko Kotani; Jumpei Yamamoto (AKCE Int. J. Graphs Comb., 2024)