El-Shafei, M.E., Zakari, A.H. (2011)

International Journal of Mathematics and Mathematical Sciences

Caldas Cueva, Miguel (2000)

International Journal of Mathematics and Mathematical Sciences

Rosas, Ennis, Carpintero, Carlos, Sanabria, José (2007)

Bulletin of the Malaysian Mathematical Sciences Society. Second Series

Baker, C.W. (1994)

International Journal of Mathematics and Mathematical Sciences

Daraby, Bayaz (2010)

Acta Universitatis Apulensis. Mathematics - Informatics

Petre C. Osmatescu (1969)

Czechoslovak Mathematical Journal

З.И. Боревич (1977)

Zapiski naucnych seminarov Leningradskogo

З.И. Боревич (1982)

Zapiski naucnych seminarov Leningradskogo

З.И. Боревич (1980)

Zapiski naucnych seminarov Leningradskogo

Дж. Хаджаев, Т.М. Шамилев, Dž. Chadžiev, T. M. Šamilev, Dž. Hadžiev, T. M. Šamilev, Dž. Chadžiev, T. M. Šamilev (1997)

Algebra i Logika

А.Н. Долгушев (1979)

Sibirskij matematiceskij zurnal

Otokar Grošek (1978)

Mathematica Slovaca