Eulerian Numbers Associated with Arithmetical Progressions. - José Luis Ramírez; Sergio N. Villamarin; Diego Villamizar (Electron. J. Comb., 2018)

Extensions of Set Partitions and Permutations. - Jhon B. Caicedo; Victor H. Moll; José Luis Ramírez; Diego Villamizar (Electron. J. Comb., 2019)

A refinement of Dyck paths: A combinatorial approach. - Rigoberto Flórez; José Luis Ramírez; Fabio A. Velandia; Diego Villamizar (Discret. Math. Algorithms Appl., 2022)

Counting Colored Tilings on Grids and Graphs. - José Luis Ramírez; Diego Villamizar (GASCom, 2024)

Colored Random Tilings on Grids. - José Luis Ramírez; Diego Villamizar (J. Autom. Lang. Comb., 2024)

Restricted bargraphs and unimodal compositions. - Rigoberto Flórez; José Luis Ramírez; Diego Villamizar (J. Comb. Theory, Ser. A, 2024)

The combinatorics of Motzkin polyominoes. - Jean-Luc Baril; Sergey Kirgizov; José Luis Ramírez; Diego Villamizar (Discret. Appl. Math., 2025)