APA (7th ed.) Citation

Keller, H., & Kruger, S. (2002). ABAP Objects: Introduction to programming SAP applications. Addison-Wesley.

Chicago Style (17th ed.) Citation

Keller, Horst, and Sascha Kruger. ABAP Objects: Introduction to Programming SAP Applications. London: Addison-Wesley, 2002.

MLA (8th ed.) Citation

Keller, Horst, and Sascha Kruger. ABAP Objects: Introduction to Programming SAP Applications. Addison-Wesley, 2002.

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