1. Manchanda Y, Das S, De A. Coronavirus disease of 2019 (COVID-19) facts and figures: What every dermatologist should know in this hour of need.
2. Ammerman BA, Burke TA, Jacobucci R, McClure K. Preliminary Investigation of the Association Between COVID-19 and Suicidal Thoughts and Behaviors in the US.
3. Epidemiology, causes, clinical manifestation and diagnosis, prevention and control of coronavirus disease (COVID-19) during the early outbreak period: a scoping review;Adhikari;Infectious Dis Poverty,2020
4. Miller KS, Ross B. Fractional difference calculus. In: Proceedings of the international symposium on univalent functions, fractional calculus and their applications 1988 May (pp. 139–152).
5. Discrete fractional calculus with the nabla operator;Atici;Electron J Qual Theory Diff Eqs,2009