@Article{JMS-53-i,
author = {},
title = {Preface},
journal = {Journal of Mathematical Study},
year = {2020},
volume = {53},
number = {4},
pages = {i--i},
abstract = {},
issn = {2617-8702},
doi = {https://doi.org/},
url = {http://global-sci.org/intro/article_detail/jms/18505.html}
}