Ullrich, O; Thiel, C S (2012). Gravitational force: Triggered stress in cells of the immune system. In: Chouker, A. Stress challenges and immunity in space : from mechanisms to monitoring and preventive strategies. Berlin, DE: Springer, 187-202.
Thiel, C S; Ehrenfreund, P; Foing, B; Pletser, V; Ullrich, O (2011). PCR-based analysis of microbial communities during the EuroGeoMars campaign at Mars Desert Research Station, Utah. International Journal of Astrobiology, 10(3):177-190.