Perner, Josef MPI for Psychological Research (Munich, -2003), The Prior Institutes, Max Planck Institute for Human Cognitive and Brain Sciences, Max Planck Society;
Perner, J., & Wimmer, H. (1985). John Thinks That Mary Thinks That - Attribution of 2nd-Order Beliefs by 5-Year-Old to 10-Year-Old Children. Journal of Experimental Child Psychology, 39(3), 437-471.