Here are examples of how to refer to an entire book. Books are seldom the primary source for research results (journal articles are), but they are popular and can provide summaries of theories and research. You can use research method textbooks, for example, when you write your method chapter.
This development started in the middle of the 20th century (Ciabattari, 2021). It has also been discussed by Buchanan and Badham (2021).
Buchanan, D., & Badham, R. (2021). Power, Politics, and Organizational Change (3rd ed.). Sage Publications.
Ciabattari, T. (2021). Sociology of Families: Change, Continuity, and Diversity (2nd ed.). Sage Publications.
This can be compared to previous results (Berman et al., 2021). It has also been discussed by Berman et al. (2021).
Berman, E. M., Bowman, J. S., West, J. P., & Van Wart, M. R. (2021). Human Resource Management in Public Service: Paradoxes, Processes, and Problems (7th ed.). Sage Publications.