Cita APA (7a ed.)

Ullrich, F., & Schwalm, H. (2011). Legacy swarm for the Ruhrgebiet: Bob Braine, Mark Dion & GFLK Surveys. Kettler.

Cita Chicago Style (17a ed.)

Ullrich, Ferdinand, y Hans-Jürgen Schwalm. Legacy Swarm for the Ruhrgebiet: Bob Braine, Mark Dion & GFLK Surveys. Bönen: Kettler, 2011.

Cita MLA (8a ed.)

Ullrich, Ferdinand, y Hans-Jürgen Schwalm. Legacy Swarm for the Ruhrgebiet: Bob Braine, Mark Dion & GFLK Surveys. Kettler, 2011.