DiLeo, C., & Cooper, P. (2020). Beginning Ruby 3: From Beginner to Pro (4th edition.). Apress.
Chicago Style (17th ed.) CitationDiLeo, Carleton, and Peter Cooper. Beginning Ruby 3: From Beginner to Pro. 4th edition. Apress, 2020.
MLA (9th ed.) CitationDiLeo, Carleton, and Peter Cooper. Beginning Ruby 3: From Beginner to Pro. 4th edition. Apress, 2020.
Warning: These citations may not always be 100% accurate.