APA (7th ed.) Citation

Ahrens, F., & Walter, H. (1971). Datenbanksystem. de Gruyter.

Chicago Style (17th ed.) Citation

Ahrens, Friedhelm, and Helmut Walter. Datenbanksystem. Berlin [u.a.]: de Gruyter, 1971.

MLA (9th ed.) Citation

Ahrens, Friedhelm, and Helmut Walter. Datenbanksystem. de Gruyter, 1971.

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