Cite Them Right 11th edition - Harvard

Sloan Kelly and Sloan Kelly (2019) Python, Py Game, and Raspberry Pi Game Development.

Chicago Manual of Style 17th edition (full note)

Sloan Kelly, and Sloan Kelly. Python, Py Game, and Raspberry Pi Game Development.

American Psychological Association 7th edition

Sloan Kelly, & Sloan Kelly. (2019). Python, Py Game, and Raspberry Pi Game Development.

Modern Language Association 9th edition

Sloan Kelly, and Sloan Kelly. Python, Py Game, and Raspberry Pi Game Development. 2019.

ISO-690 (author-date, Deutsch)

SLOAN KELLY and SLOAN KELLY, 2019. Python, Py Game, and Raspberry Pi Game Development

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