Some Properties of Spectral Binary Relations. - Karim Belaid; Bahri Cherif; Othman Echi (RelMiCS, 1997)

T(α, β)-spaces and the Wallman compactification. - Karim Belaid; Othman Echi; Sami Lazaar (Int. J. Math. Math. Sci., 2004)

The envelope of a subcategory in topology and group theory. - Ahmed Ayache; Othman Echi (Int. J. Math. Math. Sci., 2005)

Two classes of locally compact sober spaces. - Karim Belaid; Othman Echi; Riyadh Gargouri (Int. J. Math. Math. Sci., 2005)

Universal mapping properties of some pseudovaluation domains and related quasilocal domains. - Ahmed Ayache; David E. Dobbs; Othman Echi (Int. J. Math. Math. Sci., 2006)

On the minimality of Hamming compatible metrics - Parsa Bakhtary; Othman Echi (CoRR, 2012)

On minimal Hamming compatible distances. - Parsa Bakhtary; Othman Echi (RAIRO Theor. Informatics Appl., 2014)

Non-primitive words of the form pqm. - Othman Echi (RAIRO Theor. Informatics Appl., 2017)

On primitive words with non-primitive product. - Othman Echi; Adel Khalfallah; Dhaker Kroumi (RAIRO Theor. Informatics Appl., 2022)

The Primitive Deficiency of two Primitive Strings. - Othman Echi (Acta Informatica, 2025)