19 Feb 2020
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Cho Eun-Kyung
•
Choi Ilkyoo
•
Jiang Yiting
•
Kim Ringi
•
Park Boram
•
Yan Jiayan
•
Zhu Xuding
This paper disproves a conjecture of Wang, Wu, Yan and Xie, and answers in
negative a question in Dvorak, Pekarek and Sereni. In return, we pose five open
problems...