Rugoff, R. (2009). Johannes Kahrs: With an essay by Ralph Rugoff. Hatje Cantz Verlag.
Chicago-viite (17. p.)Rugoff, Ralph. Johannes Kahrs: With an Essay by Ralph Rugoff. Ostfildern: Hatje Cantz Verlag, 2009.
MLA-viite (8. p.)Rugoff, Ralph. Johannes Kahrs: With an Essay by Ralph Rugoff. Hatje Cantz Verlag, 2009.
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