W. R. Uttal 
The Detection of Nonplanar Surfaces in Visual Space [EPUB ebook] 

First published in 1984. This monograph is the third in a series that examines the nature of a midlevel visual process relatively uncontaminated by either peripheral receptor or central cognitive processing. The paradigm utilized in this study selectively assays what seems to be a relatively fixed algorithmic mechanism involved in the extraction of dotted stimulus-forms from masks consisting of random dots.