Gan, Xiao-Xiong. "1 Basics of formal power series". Formal Analysis: An Introduction, Berlin, Boston: De Gruyter, 2021, pp. 1-48. https://doi.org/10.1515/9783110599459-001
Gan, X. (2021). 1 Basics of formal power series. In Formal Analysis: An Introduction (pp. 1-48). Berlin, Boston: De Gruyter. https://doi.org/10.1515/9783110599459-001
Gan, Xiao-Xiong. "1 Basics of formal power series" In Formal Analysis: An Introduction, 1-48. Berlin, Boston: De Gruyter, 2021. https://doi.org/10.1515/9783110599459-001