APA (7th ed.) Citation

Zapf, D., & Leymann, H. (1996). Foreword. [s.n.].

Chicago Style (17th ed.) Citation

Zapf, Dieter, and Heinz Leymann. Foreword. [S.l.]: [s.n.], 1996.

MLA (9th ed.) Citation

Zapf, Dieter, and Heinz Leymann. Foreword. [s.n.], 1996.