Erratum to: Chapter 4 in: E. Grigorieva, Methods of Solving Number Theory Problems, https://doi.org/10.1007/978-3-319-90915-8_4

In the original version of the book, the term “convergence” has to be updated as “congruence” under Sect. 4.3.2. in Chapter 4. The erratum chapter and the book have been updated with the change.