**Selected Papers from IIKII 2019 conferences in Symmetry**

Special Issue Editors

**TeenHang Meen Charles Tijus Jih-Fu Tu**

MDPI • Basel • Beijing • Wuhan • Barcelona • Belgrade • Manchester • Tokyo • Cluj • Tianjin

*Special Issue Editors* TeenHang Meen National Formosa University Taiwan

Charles Tijus Universite Paris 8 ´ France

Jih-Fu Tu St. John's University Taiwan

*Editorial Office* MDPI St. Alban-Anlage 66 4052 Basel, Switzerland

This is a reprint of articles from the Special Issue published online in the open access journal *Symmetry* (ISSN 2073-8994) (available at: https://www.mdpi.com/journal/symmetry/special issues/IIKII 2019 conferences).

For citation purposes, cite each article independently as indicated on the article page online and as indicated below:

LastName, A.A.; LastName, B.B.; LastName, C.C. Article Title. *Journal Name* **Year**, *Article Number*, Page Range.

**ISBN 978-3-03936-240-0 (Hbk) ISBN 978-3-03936-241-7 (PDF)**

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