Southworth, K., Dluglos, C., Fröhlich, E., Hermes, H., Kain, K., Koenig, W., & Sunder-Plassmann, A. (1990). City focus: Six photographers from West Berlin : Caroline Dlugos, Elfi Frölich, Heinrich Hermes, Karawahn Kain, Wilmar Koenig, Andrea Sunder-Plassmann. Collins Gallery.
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)Southworth, Karen, Caroline Dluglos, Elfi Fröhlich, Heinrich Hermes, Karawahn Kain, Wilmar Koenig, và Andrea Sunder-Plassmann. City Focus: Six Photographers from West Berlin : Caroline Dlugos, Elfi Frölich, Heinrich Hermes, Karawahn Kain, Wilmar Koenig, Andrea Sunder-Plassmann. [Glasgow]: Collins Gallery, 1990.
Trích dẫn kiểu MLA (xuất bản lần thứ 8)Southworth, Karen, et al. City Focus: Six Photographers from West Berlin : Caroline Dlugos, Elfi Frölich, Heinrich Hermes, Karawahn Kain, Wilmar Koenig, Andrea Sunder-Plassmann. Collins Gallery, 1990.