Cite Them Right 11th edition - Harvard

Saverio Perugini and Saverio Perugini (2021) Programming Languages: Concepts and Implementation.

Chicago Manual of Style 17th edition (full note)

Saverio Perugini, and Saverio Perugini. Programming Languages: Concepts and Implementation.

American Psychological Association 7th edition

Saverio Perugini, & Saverio Perugini. (2021). Programming Languages: Concepts and Implementation.

Modern Language Association 9th edition

Saverio Perugini, and Saverio Perugini. Programming Languages: Concepts and Implementation. 2021.

ISO-690 (author-date, Deutsch)

SAVERIO PERUGINI and SAVERIO PERUGINI, 2021. Programming Languages: Concepts and Implementation

Warning: These citations may not always be 100% accurate.