Protzen, J., & Harris, D. J. (2010). The universe of design: Horst Rittel's theories of design and planning. Routledge.
Chicago Style (17th ed.) CitationProtzen, Jean-Pierre, and David J. Harris. The Universe of Design: Horst Rittel's Theories of Design and Planning. Oxon [England] New York, N.Y: Routledge, 2010.
MLA (9th ed.) CitationProtzen, Jean-Pierre, and David J. Harris. The Universe of Design: Horst Rittel's Theories of Design and Planning. Routledge, 2010.
Warning: These citations may not always be 100% accurate.