Tyler, C. W., & Chen, C.-C. (2006). Spatial summation of face information. Journal of Vision, 6(10):11, 1117-1125, http://journalofvision.org/6/10/11/, doi:10.1167/6.10.11.
http://journalofvision.org/6/10/11/
http://journalofvision.org/6/10/11/