Diversity and habitat specificity of free-living protozoa in commercial poultry houses., Baré, Julie, Sabbe Koen, Van Wichelen Jeroen, van Gremberghe Ineke, D'hondt Sofie, and Houf Kurt , Appl Environ Microbiol, 2009 Mar, Volume 75, Issue 5, p.1417-26, (2009)