APA (7th ed.) Citation

Greenwood, K. (1999). Sams teach yourself ABAP/4 in 21 days. Sams Pub..

Chicago Style (17th ed.) Citation

Greenwood, Ken. Sams Teach Yourself ABAP/4 in 21 Days. Indianapolis, Ind.: Sams Pub., 1999.

MLA (9th ed.) Citation

Greenwood, Ken. Sams Teach Yourself ABAP/4 in 21 Days. Sams Pub., 1999.

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