@Article{JMS-49-4, author = {}, title = { Preface}, journal = {Journal of Mathematical Study}, year = {2016}, volume = {49}, number = {4}, pages = {0--0}, abstract = {}, issn = {2617-8702}, doi = {https://doi.org/2016-JMS-10115}, url = {https://global-sci.com/article/87807/preface} }