by Chang, Yu-Hsien, Hong, Cheng-Hong
Published in Taiwanese journal of mathematics (01.10.2012)

by Dell’Oro, Filippo, Pata, Vittorino
Published in Milan journal of mathematics (01.12.2017)

by Danese, Valeria, Dell'Oro, Filippo
Published in Proceedings of the Royal Society of Edinburgh. Section A. Mathematics (01.08.2017)

by Benmerrous, A, Elomari, M
Published in TWMS journal of applied and engineering mathematics (01.07.2025)